S20 FE 5g - WiFi Calling issues - Could it be the handset?

[StoufferTheCat]

Hi,
I took delivery of a new S20 FE on Friday last week - since then I've not been able to get WiFi calling working.
I am with Asda Mobile and they have tried a number of things, however the WiFi calling options will not appear on the handset. However, on completing some further testing, beginning to wonder if it could be the handset?

Take a Vodaphone SIM that is working with WiFi calling in another handset. Installed that into the S20 FE - no WiFi calling options. Completed a couple of restarts, no options appear.

Took Asda mobile SIM and plugged that into a Samsung A12. The A12 received two CS messages from Asda Mobile - installed these, WiFi calling options available.
Removed Asda SIM, reinserted into the S20 FE - still no options available.

Removed all SIM's from the S20 FE and completed a full factory reset. Went through the basic setup and then reinstalled the Asda SIM - still no WiFi calling options.

The only odd thing is that when I inserted the Asda Mobile SIM into the A12, within seconds there were two CS messages from Asda Mobile, which I installed.
When I reinserted the Asda Mobile SIM into my S20 FE after the factory reset I didn't receive any CS messages, nothing at all.
However - the fact I can take this Asda SIM and insert it into another handset and get the WiFi calling issues and I take a SIM from an old A20e (with WiFi calling working) and insert and still don't have any options. Is this looking like a potential handset issue?

I don't unfortunately have an EE SIM I can try - I know EE's network seems to work differently with WiFi calling and stuff "just works" as opposed to Vodafone/Asda where features need to be activated etc.
There isn't a way I can force the CS messages to be downloaded to a phone I'm assuming?

[Andy3]

It's not the handset WiFi calling is purely carrier specific. You need to contact asda mobile and get them to enable WiFi calling. If its enabled on there end you need to get asda mobile to disable and enable WiFi calling if that sill does not work then you need to change sim cards. WiFi calling is completely carrier/sim card specific.

[Andy3]

Asda mobile does not support WiFi calling yet as seen here https://www.ispreview.co.uk/talk/threads/cant-get-wifi-calling-with-asda-vodafone.38121/

[BrianHD88]

EE the only network I know that's WiFi calling probably others but have to ask the providers

[BrianHD88]

If the wi fi on your call logs show how I've circled then you phone carrier does it if not out of luck

[StoufferTheCat]

Yer - they do - https://mobile.asda.com/wifi-calling
As I mentioned, if I move my Asda SIM into a spare A12 mobile and accept the two CS messages that seem to get automatically sent, WiFi calling appears. However, pop the SIM back into the S20 FE and no options.

[Andy3]

You should have a WiFi calling option on thos area

[BrianHD88]

And how I circle it as well

[Mel1791]

My S20 Ultra lost WiFi calling after working for over 2 years until a Vodafone tech advisor damaged my sim. Now on second new sim. They say that they've done everything on their end. So must be my handset. Yet worked fine with my old Vodafone sim. I need it as I'm disabled and my nearest 4G signal is over 5 miles away from my house.