Why is wrong country code causing my texts to not be sent?

This question has been asked before, but the directions provided are a problem for me. I have been in Mexico, and still have a Mexican SIM on my phone, though my US eSIM is primary. After returning I've been sending texts without trouble in the US, but today I cannot text someone here in the US because the number has +52 in front of it. When I try to look at my account setting, the message says I have to cancel my Music account before I can do so. My Music subscription is in the US. Every other relevant setting I can locate is set to the USA. What next?