Garmin logo freezes even when doing Master Reset


I've been using my Fenix 5 Plus for a year and a half with no problems and suddenly, after synchronising a track and when I was about to start the activity, the Garmin logo appeared completely frozen on the screen. Nothing I tried to do worked until after living it off for a few hours I could properly do a Master Reset. 

After "initializing maps" it comes back to the Garmin Logo...

I don't know what to do, as any technique using buttons apparently doesn't work.