Suddenly unable to make or receive calls

Hi, I’ve been having this issue for the last few weeks, only realised this issue last week as it’s only happening on 2 mobiles that my daughters are using and they both are overseas phones.  My S23 ultra UK version also has ID mobile SIM and is working fine.

Their phones are Oppo android phones, SMS and Internet are working fine. only making and receiving calls that are not working.

I’ve called customer service and all they have offered is SIM replacement which I don’t think will sort the issue out. talking to them felt like talking to a brick wall unfortunately. Was not getting anywhere.

I’ve tried the code that @mm141 tried but to no avail. Not sure what else to do here.

Any thoughts?

quick update: so I’ve just transferred the sim card to another phone (my work phone) which is an old Samsung A53. I also couldn’t make nor receive calls. But using my work SIM which is on EE works fine. 

looks like I will need to jump ship from ID mobile, but jumping to three is not going to help I think given that they’re using three infrastructure.

@notworking -

Would recommend following the steps in this guide:

• 3G is being switched off and I can't make calls. What do I need to do? F.A.Q.

Thanks.

unfortunately I tried everything there and none of them worked. it seems like it will only work if your phone has got 5G or VoLTE. if you have a 4G phone or if you disable VoLTE, it work work.

Hi @notworking 

That would be more or less correct, what device are you trying to use that isn’t working?

Tom

I can confirm exactly this, as above.  It is replicable.

I’m using a Samsung Galaxy S10 and it has worked perfectly fine with VoLTE switched off, on all networks (I have tried all but O2).  I always had VoLTE switched off as I was worried it would use up my data allowance.

Depending on where I have been (Uk and EU) then the phone will not make or receive voice calls, but SMS and data have been fine.  Within the Midlands (I’m Derbyshire) it just doesn’t work.

Switching on VoLTE and it works a treat, with ‘HD+’ coming up on the display when a voice call is made or received.  If i switch off VoLTE then it breaks again.

So, I hope this helps someone.  If you have VoLTE off, try switching it on.  I suspect that many modern handsets have it on by default or do not even give that option.

@Kalico -

Thanks for sharing your insights.

I fixed mine by buying new phone that has volte capability. It's clearly says on their website that the most must have volte capability. Whether you enable it or not, it's another matter. Which is very annoying because if it doesn't use volte feature, then why does it need to have volte capability?

@notworking -

After the 3G Switch Off, VoLTE is required to make calls over 4G. Thanks.