Upgrading to iOS 15.6.1 call failure on my outgoing calls using cellular but calls connect when using WiFi calling

Is anyone else having this issue?

Immediately after upgrading to iOS 15.6.1, call failure on some of my outgoing calls using cellular but same calls connect when using WiFi calling. Issue persists after restarting my iPhone 12 mini 3 times.

Also, to Apple, when's the next upgrade to fix this issue.