Thank you for reaching out on the Community Forums! After going through research on the unknown sender and messages, I was able to find a thread with some helpful troubleshooting steps to get this resolved for you. Click here to view the thread.
If you have any further question please feel free to reach back out to us!
Traci, AT&T Community Specialist
Need help? Ask a question to get help from the AT&T Community or support from AT&T specialists. If this reply helped you please use Accept solution to mark it as an Accepted Solution.
*I am an AT&T employee, and the postings on this site are my own and don't necessarily represent AT&T's position, strategies or opinions.