Unlocking sim – Data work after the SIM card switchover on the US cell, but on the 97 text error?

I have two of the same models of a phone (motorcycle z2 force). The one with the service has battery problems, and out of warranty. I decided to try my luck to swap the SIM card. To my amazement, the data works. However, when sending me a message, the error 97 has occurred.

I tried CDMA by resetting it, but that did not help. My best guess is that IMEI is incompatible. Will I be able to forgive my old phone in any way? Try to customize the operating system to give my other IMEI phones or something like that? Or am I SOL (I can not activate this phone, outstanding bill) as far as I know, Motorola is sold unlocked on US Cellular.