Update 1/21 @ 7:35 PM ET: Seems servers are back and running!
It’s not just you! Google and PTC authentication is failing worldwide, travelers, due to an alleged security certificate lapse. Those currently logged-in are no longer receiving in-game data or responses.
— The Silph Road (@TheSilphRoad) January 22, 2018
Trainers around the world have experienced downtime in Pokémon GO with their PTC (Pokémon Trainers Club) and Google accounts as reported by The Silph Road. From what it seems, Pokémon GO is currently experiencing downtime with their authentication servers, similar issues since it’s initial launch.
Due to the Pokémon GO’s authentication servers being down, players are not able to log-in or receive any in-game data responses. The cause of this is still unknown, however, we’ll provide more updates as it’s fixed.