WIfi Calling and VoLTE keep failing to work – Galaxy 21 Ultra

[jab1972]

Hi I am having a very frustrating problem with my new Galaxy 21 Ultra in that the WIfi Calling and VoLTE will only work a limited time and then both stop working.

The only way to then get them to work again is to reboot the phone,

After a reboot they both work again straight away.

They seem to stop working when I have been traveling around.

If I stay at my home location for a few days then they generally stay working but as soon as I move locations, they, at some point, will stop working again and the phone has to be rebooted.

I previously had a Note 9 for approx. 3 years and never had any issues with the Wifi Calling or VoLTE working.

I have spoken to Vodafone Customer Services on 191 a number of time and nobody seems to know how to fix this.

They have suggested carrying out a network reset, which did not help.

They have also deleted and re-enabled Wifi Calling and VoLTE on my account, this did not work either.

I have  the Wifi Calling option under call settings which is turned on.

When both services stop working, I have tried toggling the Wifi Calling option, a Network Reset, Airplane mode and back, de-selecting from the Voda network then reselecting again and nothing will make the Wifi Calling and VoLTE work again apart from a reboot of the phone.

Interestingly I don’t have the VoLTE option under network settings (or Icon when its working), although I never had these either on my Note 9 and VoLTE worked perfectly on this phone.

I also spoke to customer services about this and they said that they would send the OTA config to enable the VoLTE option as it definitely should be there, but this did not enable the option.

(When I first got the phone the Wifi Calling OTA config was also sent and this worked enabling the WIfi calling option successfully)

Should this VoLTE option and Icon be there?

I have also spoken to Samsung Customer support about this and they say there is no known software issue and all they can offer is sending the phone back to them to “re-flash the software” which would mean me being with out my phone for up to 30 days!!

I do not think it is acceptable to be sending back a 6 week old phone to the manufacture to be “repaired”.

The Wifi calling and VoLTE options are very important to me and the reason I purchased the phone though Vodafone to make sure these functions were supported.

Can anybody advise please?

Many thanks

Jason

[Evie]

Hey there @jab1972 - I understand this is an important feature for you to have, we'll certainly help in any way we can. Since you've said that when you're home it seems quite stable on WiFi calling voLTE, it could be an issue with network in the areas you're traveling to. For example if your phone disconnects from the WiFi or the 4G/LTE network isn't great in the area.

It might be worth checking our network status checker for this.

[jab1972]

Hi Evie,

Many thanks for your reply.

This issue is nothing to do with how good the mobile network or WiFi signal is.

I completely understand that VoLTE will not work in an area without 4g coverage and WiFi calling without a WiFi connection.

When both services stop working this is in an area of good 4g coverage for the VoLTE and a good WiFi connection for the WiFi calling. (Including my home location)

On rebooting the phone they instantly start working again in the same location.

It just seems that travelling with the phone is what seems to cause both services to silently "drop out" but it is very hard to pin down exsacly when they stop working.

To me this would seem to point to a software issue with the S21 ultra but Samsung say no it isn't.

Could you please comment on if I should have the VoLTE option in "Mobile networks" or is this option purposely not displayed in the Voda firmware variant?

I seem to remember that the option was there and grayed out when I first turned on the phone out of the box.

I am really at a loss as to what to do next to try and resolve this.

I have factory reset my phone twice and this has not helped, although both times I have used Samsung smart switch to set up from my Note 9.

Thanks 

Jason

[Evie]

Thank you for clarifying @jab1972 - My next suggestion would've been a factory reset but you beat me to it! I've checked on my phone (Samsung S10+) and I can't see the option of 4G calling with Mobile Networks on my settings 🤔 I have also done the most recent update. So I'm unsure if this is an issue with our network or the device.

Just to check have you tried a factory reset of your phone without restoring back up?

I've done a bit of googling and from reading some other forums I wonder if the most recent update to Android 11 may have caused voLTE to not show in settings. Other than the above troubleshooting, I'd advise to keep trying a manual roam, which I know you've tried before:

Settings - Connections - Mobile Networks - Network Operators and turn off Select Automatically > Select VodafoneUK.

If you're still having no luck, please drop us a message on social media with your full name, mobile/number and a link back to this forum thread to save you repeating yourself.

[jab1972]

OK, so yesterday I carried out another factory reset on my phone.

The only app I reinstalled was “WhatsApp” from the Google Play Store. (nothing restored from my old phone)

After the factory reset the Wifi Calling option disappeared from the “phone” settings, so obviously Wifi calling then didn’t work, but VoLTE worked fine. (Still no VoLTE option in Mobile settings though)

Today I travelled quite a lot with the phone and VoLTE worked fine all day.

I few hours ago, I rang 191 and asked them to resend the OTA config to enable the Wifi Calling option again, telling them that this was for a S21 Ultra.

After a few minutes the Wifi Calling option re-appeared and Wifi Calling worked again.

Then after another journey (obviously disconnected from Wifi) I found that the VoLTE has stopped working again (as well as the Wifi Calling when I next connected to a Wifi network).

As always, a reboot instantly restored both services. (as it always does regardless of the phone location or if it is connected to a Wifi Network or not)

As I have said previously, it is very difficult to know exactly when both services stop working but it seems that today that the VoLTE was fine until the phone received the Wifi calling option OTA config and then the phone travelled without a Wifi connection.  (when one service fails the other has always failed as well)

This is now proved to be nothing to do with Installed 3rd party apps or restoring/transferring data from my old Note 9.

There is either an issue with Samsung’s or Vodafone’s Variant firmware on the S21 Ultra possibly tiggered by the OTA pushed config to enable the Wifi Calling option? or there is something wrong with just my phone?

This needs investigation by Vodafone, if it is just a firmware bug that will be resolved with an update, then that’s fine, but at the moment this very very expensive phone is not fit for my purpose and is of no use to me functioning like this.

Is there any body else on this forum that has an S21 Ultra that suffers from this problem or is it just my phone?

I know I have now had this phone over 30 days, but I first reported this issue after approx. 2 weeks of receiving it, and if this can’t be resolved, I shall be insisting that I return my phone to Vodafone and my contract is cancelled.

Please help.

Many thanks

Jason

[Mark]

If the steps outlined by Evie haven't helped @jab1972, pop us a message through one of our social channels and we'll make sure everything is set up correctly on your account. To avoid having to repeat your self when you contact us, please include a link to this thread and your Community user name and we'll be happy to help.

[jab1972]

Hi Mark,

Thanks for your reply.

I have sent a DM via Face Book.

After further testing, this issue seems to be caused when the phone is moved around and it connects/disconnects to different known Wifi Networks.

The other day, I tested turning the Wifi Calling off in the phone settings (but leaving the Wifi on) when I was traveling around (phone was connecting and disconnecting to known Wifi networks depending on my location) and by the end of the day the VoLTE had stopped working again.

I then turned the Wifi Calling back on (whilst connected to a Wifi Network) and that wouldn't work either, again, a phone reboot instantly restored both services.

It seems that if I stay just in my house connected to my Wifi both services will stay working perfectly for days.

I just can not imagine what would cause this other than an issue with the Vodafone firmware in the S21???

[jdksajdaskdk]

Did you get to the bottom of this? I have the exact same problem with a different handset (Mi 10T Pro)

After a phone restart, VoLTE/4G Calling and Wifi Calling work for a short period, then stops working, usually after moving around between mobile towers and wifi hotspots. I've tried all the steps above except a factory reset.

I find it happens whenever the device loses mobile signal, or when the device flips down to 3g and then back to 4g, 4g data service returns but both VoLTE calling and WiFi Calling remain disconnected despite being enabled in settings.

I have a Three PAYG sim in my phone at the same time which works perfectly

Looking at the device logs (With Logcat reader), I get lines like 

QImsService] ImsServiceSub : [0] Permanent IWLAN reg failure (IKEv2 auth failure)

I also see 

IKEV2ErrorReceiver] Canadian configure is not set, return

Other things I've tried:

• Updating to the latest MIUI version (12.1.5.0)
• Network settings reset
• Only using the one sim
• Removing the Three SIM
• Clearing all caches
• Clearing caches and storage of things like CneApp, Carrier Services, Phone Services, Phone, anything carrier related
• Resetting APNs, adding APNs with bearer set
• Setting phone to prefer 4G/LTE (ie do not connect to 5G)
• Removing my VPN, same problem with VPN installed or not installed.

One way I've managed to get it stable is to dial *#*#4636#*#*, go to phone and set preferred network type to "NR/LTE".  The phone does not connect to 3G or below in this mode, and unfortunately this setting gets reset when the phone restarts.

At this point I think its a problem with the MIUI software version itself, or some firmware driver that comes with these versions of MIUI.  Perhaps the same modem software is used in the Galaxy 21 Ultra line of phones!

[Tash]

@jdksajdaskdk  Thanks for flagging this to us and I'm sorry to hear you're experiencing similar issues on your phone!

With our Wi-Fi Calling feature, this normally comes into play should your phone find the reception in the area is poor. It can sometimes help to switch to Airplane mode to force the phone to stop looking for a mobile connection and use Wi-Fi only for your calls/texts should you find your call quality is affected (for example).

With your VoLTE calls, does this happen everywhere you go or in one particular location? You mentioned your other SIM card with a different network works as normal - I'd like to check whether your 4G coverage is affected in the area(s) you're testing the feature in 👍 If you'd prefer not to share the affected postcode(s) on the thread here, you can add this to your profile where only us moderators can view it.

[jdksajdaskdk]

I have the phone set to prefer WiFi calls, and it happens in many places.  When I travel on a train for example and then arrive in a place with a strong 4g signal, 4g calling does not resume and reverts to 3g each time I make a call, until I reboot the phone.  Any time 4g calling fails to work in this way, WiFi calling is also not working