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“The interoperability issue between carriers has been resolved,” an AT&T spokesperson said. “We collaborated with the other carrier to find a solution and appreciate our customers patience during this period.”In a previous statement sent to CNN, the company said a problem prevented many AT&T customers from completing calls between carriers. That also means customers from a rival service could not place calls to an AT&T customer.
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The outage comes less than four months after a massive disruption that knocked out service for AT&T’s network for nearly 12 hours. In February, tens of thousands of AT&T customers in America were unable to make phone calls, send texts, reach emergency services or access the internet because of an AT&T network outage.
In March, the telecommunications company said it had been hacked in a separate incident, and the stolen data contained information such as account holders’ Social Security numbers.