I seem to be having this same issue. Have you made any progress yourself? I would assume you have indeed found a different app since posting, would you mind sharing what you landed on and how it works for you?
I'm running a Pixel 8a, latest stable release 2025011500, in a separate User Profile from the Owner, with a SIM card from Mint Moble.
I too tried restarting the phone to no avail, and going back into the settings and trying them on and back off seemed to do nothing.