I can imagine it must've been one ugly surprise to have that notice sprung up on you with no warning. Sorry for keeping you waiting - we needed some time to look into what led to this ban. After contacting the support, providing as much infos as I could and waiting 5 full days here's their answer: Nothing happened at the time but a few hours later I received a HWID ban. I had it running when I alt-tabbed into Valorant by mistake for about 3 seconds until I realized and stopped it.
I started playing cookie-clicker recently and used this software: to auto-click in order to get cookies faster (yes it's dumb as you can just change values).
Here's a quick thread to warn everyone to never run an auto-clicker when your game is open.