Fusion 2 Magazine stuck

Have problem with the Magazine for my new UMAREX Fusion 2. It was difficult to install and now it's stuck and I can't remove it. I shot all 9 pellets and the bolt is all the way back. Tried bumping it with a rubber mallet and it didn't move. HELP
I've put about 300 rounds through my Fusion 2 and not had that problem. With that said, can you rotate the magazine wheel 'backwards' with the bolt fully back? If not, then you might have some debris (part of a pellet? or a broken off plastic chunk of the magazine?) lodged between the front of the magazine and the chamber.

You might need to destroy the magazine bit by bit with pliers to get it out. A $9 mag is cheaper to replace than repairing part of the rifle.