T-Mobile suffered network outages on Monday night, leading to intermittent issues with its voice, text and data services, according to Reuters. Based on reports submitted to Downdetector, over 80,000 subscribers in several areas in the US were experiencing problems by around 10:14PM ET on February 14th. T-Mobile responded to users’ complaints on Twitter, initially to tell people that the carrier was working on a fix for the disruption and then to update everyone about its progress. Shortly after midnight on February 14th, Neville Ray, the company’s President of Technology, announced that T-Mobile has seen “significant improvement and are operating at near normal levels.”

Indeed, the number of outage reports on Downdetector dramatically went down after its peak at 10PM on Monday. Ray said the outage was caused by a third-party fiber interruption issue that affected its services — for some people, even emergency numbers were inaccessible. The outages also seemed to have affected not just T-Mobile’s own customers, but people who use MVNOs that rely on the carrier’s network, as well. 9to5Google says Google Fi users have also been experiencing intermittent access to its services, though they’ll likely be able use them as usual soon, if T-Mobile truly was able to fix the problem.