Hello everyone! I've been using my Galaxy S9 Plus (dual sim international model) with diffent sim cards (Chinese LTE (China Mobile) and Ukrainian Vodafone and Kyivstar) since the beginning of 2018.
Since the end of last year, I couldn't make or receive any calls on all sim cards.. The 4G Internet and masseges works just fine, but when I am trying to call someone or other people call me, there are no ringtone, just silence, and it doesn't connect. I‘ve already tried hard reset, switching sim cards, tried all kinds of APN settings. No changes.
Searching the forums made me think that the problem might be related to the new VoTLE function. Because while I am in China using Chinese LTE sim card, when I enable "VoLTE" I still can make calls, but after I turn if off, there are no way to make or recieve calls. While using Ukrainian sim cards there are no VoLTE option available in the settings at all, so still no way to make/receive calls (changing network to 2G/3G doesn't make any changes). Before, in 2018 and till the end of 2019 everything worked just fine.
If anyone has any suggestions on how to fix this problem, please, share your opinion. Thanks in advance!