Are there any Taiwan Mobile customers here that have experienced not being able to make or receive phone calls from your mobile phone?
I’m referring to using the phone app, not VOIP apps.
I’ve noticed that recently, many people I know that are using Taiwan Mobile can no longer make or receive calls even though their mobile data connection is working fine.
What phone are you using, and does it support wifi calling? There’s been an issue with 3G being shut down, and voice using VOLTE exclusively, and not all phones support VOLTE, and if yours don’t, your phone stopped working when 3G is phased out.
Chunghwa Electronics, Taiwan Telecom, and Far EasTone all announced today that they are expected to shut down 3G networks before June 30, 2024.
After telecom operators shut down 3G networks, users’ voice calls will be fully conducted through 4G calls (VoLTE).
I’m a Taiwan Mobile user and noticed this last week. I rarely use my phone’s call feature, so I’m not sure how long it wasn’t working. Anyway, after some trial and error I discovered this setting in the image below was turned off, even though I had never touched it and didn’t even know what it was.
That may not even be related to Taiwan Mobile, but it solved the problem for me.
EDIT: I see this is addressed in the comments above.
That’s another thing too, older phones might support VOLTE but are not enabled by default. I had a HTC phone that was like this, works with VOLTE but you have to find the setting which is buried deep in their menu and are not enabled by default. Matters more when you are using wifi in an area with poor cell reception.
Thanks everyone! Your responses helped me to fix my problem. 
My wife and I had same problem with our phones. We just returned from overseas and thought perhaps that was why we were having a problem. I went to Taiwan Mobile and he fixed the problem which was exactly what above posts said. Good to know it was not just us
