If your T-Mobile service was having issues on Monday, you were not alone. The third-largest wireless carrier is seemingly having widespread issues around the country impacting the ability to make calls and text.
It is unclear what caused the issue or when it will be resolved. Users across the country took to Twitter to note the outage, with T-Mobile rising to the top spot on the site’s US Trending Topics as of 9:00 p.m. ET.
The main issue appears to be with calls and texts, with users saying that data was working normally.
Neville Ray, T-Mobile’s president of technology, acknowledged in a tweet that the carrier was having an outage and said that the carrier “hopes to have this fixed shortly.”
In a tweet sent shortly after 6 p.m. ET, Ray says the carrier was still working to fix calls and texts, while recommending that users use apps like FaceTime, WhatsApp and iMessage to communicate.
Those apps, unlike traditional SMS text messages or voice calls, send messages and calls through the data side of the network which is still operational.
A CNET editor in New York City was able to send texts and iMessage using an iPhone, but calls were not working on either device. An editor in the San Francisco Bay Area noted that calls were not working over Google Fi, the cell phone service offered by Google that relies on T-Mobile, Sprint and U.S. Cellular’s respective networks. Data and texts over Fi, however, was working.
In addition to Google Fi, T-Mobile is the underlying network providing service for several other carriers such as its Metro prepaid brand as well as for Mint Mobile and Simple Mobile.
AT&T and Verizon each say that their respective networks are operating normally and without issues. Tests in northern New Jersey on AT&T and Verizon phones showed no issues with calls, texts or data except when trying to text or call a T-Mobile phone.
“Verizon’s network is performing well. We’re aware that another carrier is having network issues,” a Verizon spokeswoman told CNET in a statement. “Calls to and from that carrier may receive an error message.”
The company also took issue with Downdetector’s spreading that its network is having outages. “Sites such as Downdetector.com utilize limited crowdsourced data drawn from sample social posts which are often statistically insignificant or factually incorrect,” the spokeswoman said.
“A lot of factors can contribute to a false report on a third-party website,” adding that by simply aggregating this data “the result can be faulty reports of network performance interruptions causing wide-spread miscommunication for wireless users.”
T-Mobile referred back to Ray’s tweet when asked for comment. Sprint, which is now owned by T-Mobile, did not immediately respond to a request for comment.
What went wrong? A possible configuration issue but not an attack
Matthew Prince, co-founder and CEO of web infrastructure and security firm Cloudflare had a possible reason for the issue: a change in T-Mobile’s network configuration that went wrong.
After rumors circulated online that outage was a result of an attack on America’s communications networks, Prince took to the social network to note that he believes the “reality is far more boring.”
“They were making some changes to their network configurations today,” he writes in a second tweet. “Unfortunately, it went badly. The result has been for around the last 6 hours a series of cascading failures for their users, impacting both their voice and data networks.”
The outage then led to people complaining on Twitter and Downdetector which further added to the rumor that a Distributed Denial-of-Service (or DDoS) attack was underway to take down T-Mobile’s network. Prince says Cloudflare didn’t see traffic spikes on “any of the major Internet Exchanges” that would usually occur if such an attack were actually taking place.
Instead, he surmises that T-Mobile’s troubles were from the carrier “having a bad day almost certainly entirely of their own team’s making,” but not one brought on by any outside attack.
T-Mobile declined to comment when about Prince’s tweets.