Unable to manually set DNS

[Sovz400]

Hi,

I have deployed a Raspberry Pi and I am running Pi Hole as a network wide ad blocker. I have logged on to my Vodafone Broadband router and set the DNS to manual, in the server 1 field, I entered the IP address of the Pi and clicked save but I get the error in the attached picture. 

Any ideas on how to change this?

The Pi is working as if I manually set the DNS on my phone, it runs through the Pi with no issues. 

Thanks

Chris

[Sovz400]

It doesn't seem to allow me to add the pic. The error is

Correction needed

Invalid value.

[Tash]

@Sovz400 There's something we can try to stop this error from appearing.

Please switch your DNS to default rather than manual. After that, you'll be able to apply 8.8.8.8 and 8.8.4.4 - please let me know if this helps.