AT&T resolves 'nationwide issue' affecting calls between different cellphone services

The cellphone company AT&T announced on Tuesday that it had resolved a nationwide issue that affected calls between different carriers, which did not affect anyone trying to call 911.

The issue, which was not a nationwide outage but affected some callers across the country, did not impact customers' ability to text, connect to broadband for first responders, ability to make emergency calls, or call another person that used AT&T, the company said. It mostly affected AT&T users trying to connect to people using Verizon, NBC News reported.

"The interoperability issue between carriers has been resolved," the company said in a statement. "We collaborated with the other carrier to find a solution and appreciate our customers patience during this period."

Verizon said that its network had been operating properly, but that some customers were having problems connecting to those who use another service. The customers most impacted were in the Northeast and Midwest.

The Federal Communications Commission (FCC) said it was looking into the incident. It is not clear how many people were affected.

"We’re aware of reports that consumers in multiple states are unable to make wireless calls and we are currently investigating," the FCC posted on X.

The temporary issue comes nearly three months after thousands of AT&T users experienced widespread outages. That problem was related to a processing error. It is not clear what caused Tuesday's incident.