Can't Cast Spells on Project 1999

[Kenny20]

I'm having a strange issue with my character on Project 1999. I'm a level 15 Wizard on the Blue server name Faerlina, and for some reason, I can't cast any spells! My mana bar is full, and I have all the spells memorized, but whenever I try to cast them, nothing happens. I've tried relogging and checking my keybindings, but nothing seems to work.
Has anyone else encountered this problem before? Is there a specific setting I might have accidentally toggled that's preventing me from casting? Any advice would be greatly appreciated!