We plan to release a new version for our Android softphone around the next weekend which should fix all these issues. We made lot's of improvements regarding multi-account handling and configuration.

I just installed the latest version of the Mizu VOIP softphone and configured 2 SIP accounts.

The multiple accounts feature still doesn't work.

Only the account that is shown as "main account" can receive calls. The phone does not ring when I call the 2nd SIP account.

If I configure the other account as main account this one receives calls but the 1st one again doesn't.

So both accounts work if they are the main account but the 2ndary account never works.

I just installed MizuDroid 2.8.3 and can confirm that multiple accounts don't work. There seems a problem when registering the background accounts, because the Authorization is invalid. I see lots of REGISTER -> 401 Unauthorized attempts for the background accounts. The primary account always registers fine.

We are going to release a major new version tomorrow. I think it is worth to wait for this.
Then to be able to receive calls on all account, you should use background service listener (and not the push notification as push notifications for multiple accounts are not implemented yet)