AT&T customers nationwide are experiencing problems with 9-1-1 services.
Although there haven't been any reports of the San Antonio area having this issue, SAPD is letting San Antonio residents know that they can call 210-207-SAPD (7273) if they cannot reach 9-1-1 in an emergency.
Update:
AT&T says that the issue has been resolved for those that were previously having problems:
Issue has been resolved that affected some calls to 911 from wireless customers. We apologize to those who were affected.
— AT&T (@ATT) March 9, 2017