I'm using multisim, and since Maxis stopped 3G in its network, I have been having terrible experience.
I use my iPhone for Zoom/Microsoft Teams video conference, but every time there's an incoming call, the video conference on Zoom/MTeams would get disconnected as the incoming call makes my phone switch to 2G network. This is so disruptive, as every time I get disconnected, I need to wait for the host of Zoom/MTeams to allow me to rejoin. You can imagine how irritated the host gets if my connection gets disconnected too many times.
I have called Maxis CS and followed the suggestion here on the forum and asked to talk to people at Network Department. But I still have no luck getting them to enable VoLTE for my line, due to multisim.

I use the additional sims for my family's iPads.
Maxis just told me that in order to have VoLTE for my line, I need to give up multisim for my line. But Maxis also has stopped offering multisim, so I can't subscribe to another line and apply the multisim to the new line.
Do you guys have any better ideas e.g. where I get to have VoLTE for my existing line and also have sims (I need two) for iPads? Do other providers (Digi, UMobile, etc) have a solution for my situation?
Thanks!