The network outage was related to the company’s 5G rollout, Deutsche Telekom AG Chief Executive Officer Tim Hoettges said in a press conference.

Source: T-Mobile outage, now resolved, related to 5G rollout –

Update: T-Mobile itself says a fiber line went down and led to an IP traffic storm as data flowed onto what were supposed to be redundant circuits. It’s possible there was a 5G issue in this too, but that is not clear.