Originally Posted by
snstearns Model number is SM-G075U
I'm guessing the "0" was a typo. The S10+ model number is SM-G
975.
The "U" indicates a carrier device for the US market. AT&T, T-Mobile, Sprint, etc... all have the "U".
A "U1" is factory unlocked for the US market. Of course the carrier models can be unlocked after-the-fact, but it's still a "U".
Still, Consumer Cellular uses both AT&T and T-Mobile towers and networks. AT&T has a list of devices that they will support on their VoLTE service, and both S10+ U and U1 models are on that list. T-Mobile is usually even more accepting of those devices, so why CC is telling you what they did is very strange indeed.
You might want to have a chat with a different rep.