Older Samsung phones not connecting to iPhone hotspot when connected on Vodafone network

[antzdj]

So for over a year I've been using a sim free Samsung note 20 ultra that was given to me, to stream with.

I would connect it to my iPhone 16 pro max (before this iPhone 14 pro max) via my Vodafone plan iPhone hotspot.

No problems until a few weeks back, it would no longer connect to the hotspot. Kept saying couldn't get ip address.

I contacted Vodafone who said it isn't them, it must be the iPhone or note.

I tried the note to two other Samsung hotspots, fine. It connects to any wifi network too. I then tried it to my wife's 16 pro (on Vodafone), will not connect, same message.

I tried 3 more Samsungs (one this year model, one last year model, and one previous year)  and my wife's iPhone (all 3 phones on Vodafone) to my iPhone hotspot, all 3 worked. So I thought it was the note that has a fault.

I also tried a Samsung (not sure on model) of the same year as the note and that too would not connect to iPhones on Vodafone, but will connect to any other network fine (so two phones, can't be a coincidence right?).

I took it to Samsung, who did all their checks, passed. The note Connected to their 2025 Samsung test phone no problems. Their test phone connected to my iPhone no problem. They said the note needed to be sent off etc or its a network issue.

I came home that night and was at a friends, all 3 have iPhones of different new and older models. The networks was Telstra x2 and Optus. The note connected to them all instantly.

I took my iPhone and Samsung note to apple to get checked, they connected the note to their store phone with a Telstra sim card fitted, connected no issues. Took my Vodafone card from my iPhone, put it in the store phone that just worked fine on Telstra, would not connect. They told me it was Vodafones problem, as no settings have changed and it should work.

So I went to the Vodafone shop who told me this  was impossible. So he tried to connect me to the store Vodafone iPhone, would not connect to the hotspot.

He then pulled out his personal iPhone connected to Vodafone, still would not connect. So any iPhone connected to Vodafone it will not connect with.

I then went into Optus who was just around the corner and the note connected to 2 phones there.

So what have Vodafone done to stop older phones connecting to iPhone only? And why?

Yes everything has been updated, hard reset, settings changed, reset, boxes ticked, online instructions followed etc etc.

Both apple and Samsung have set the phones up and both phones work with newer phones.

Vodafone are blocking something here, and when I contact them, they have no idea.

Please help.