When I checked my Hideout Bank to take some money out, the money was still there... but all the items I stored there are now gone... I know there was some nice stuff like Become Devices, Blood Moon Devices etc. in there and some consumables... the bank's slots expanded but it's empty... can someone tell me what's going on?

If you didn't do it then someone else probably did. Perhaps your account was hacked? You should submit a ticket about this.

I'm not completely sure though, I could have just moved them out to one of my mule characters because there was no space in the account bank.... so yeah. I just haven't looked into it for a rather long time.

Is there a way for GMs to check if my account had been meddled with?