Sometime last week (start of December 2025) phoning and receiving calls stopped working. I’m on Telavox Sweden on the Telenor network with an Xperia 10 iii. VoLTE doesn’t work on the device as indicated by the status in System settings/ Mobile network/4G calling(VoLTE): Not registered.
What should I do to get calls working again?
Simplest thing probably is switching to Telia/Halebop/Fello.
Yeah, it would be the quickest solution and hang on to Telia’s 2G/3G network as long as it lasts. My work is covering mobile expenses though so I’m stuck with the current operator in that respect. What the long term solution?
I also have an Xperia 10 III, I just checked the status and I can see the device is registered as “4G calling (VoLTE)”. So the problem shouldn’t be in the device itself. But I don’t know about the details of the process the operator does regarding the registration of the phone; I have a different one (T-Mobile in Czechia).
I’m using VoLTE on the 10 III just fine too, albeit on Telia. Might be the off brand operator tripping things up, even compared to baseline Telenor.
I don’t know the status of VoIP on the Xperia 10 III with SailfishOS, but it seems that it’s not complete. The real solution is to get a device (and OS) that has full support for VoIP.
(I understand that the hardware has support for VoIP, and so does SailfishOS - on other devices like the C2 - but SailfishOS may perhaps not support VoIP on that hardware.)
VoLTE works just fine on the X10iii. If it does not, it’s either an issue with the provider (likely), or a missing configuration of VoLTE for that provider.
It seems that at least one operator in the list which is on the Telenor network (Vimla!) has things working. There seems a difference between Xperia 10ii and 10iii when it comes to complementing VoLTE settings with configuration files. Am I correct that with the 10iii you can’t really do this?