Keyboard problems
Without some additional information, the only thing I can think of that would make your keyboard seem to stop working in GW2 would be a popup notification stealing the “focus” of Windows. I had some issues with an email notifier that would steal focus even though I was playing the game in full screen mode.
Check your Windows notification area and start-up Run lists and see if you have utility running that presents popup to tell you of something. Stuff like Steam, Skype, an email checker or antivirus. Just turn off the popup notifications and see if that fixes your issue.
Im playing on laptop, Dell XPS and never had this kind of issue. After last update my keyboard started to freeze, mostly after alt+tabbing. (that issue with wp was just my bad habit of switching to chrome while loading screen is running).
I’ve searched on google and found only some issues with logitech keyboards.
Sounds like you key binding got corrupted delete your local.dat file, not sure of the full path but its in APPDATA the game will creat a new on when you run the game then redo all your in game setting.
put the correct term in but not everyone has kittens
Ok, somehow i managed to fix that by… deleting google chrome. No issues on firefox. No idea if that was the real issue, but everything works fine now