Common Area Phone License and Meeting Rooms \ SignInMode

You seems to be using the latest firmware on the phone and Microsoft did another "great" solution to take your money.
https://m365log.com/teams/enforcement-of-licenses-on-teams-phones/
Now phones with the latest firmware are enforcing signin via based on license plan assigned to account.
Before this time it was possible to use normal Common Area Phone without CAP ipphonepolicy which was the solution for the main issue with CAP interface >> speed dials.
And microsoft was telling that they will add speed dial for CAPs.
Well, they've found different approach. Now you have to pay more for another bundle of license (which one? good question) and CAP license becomes quite useless.
If you want you can try to downgrade one of your phone (factory reset afterwards is must).
With old teams agent in the firmware it should not change the interface automatically.