spyder mr2 issues

[Jman21]

i have a mr2 and never use it. I pulled it out yesterday and it wont fire. electronic trigger works on all 3 modes. when a co2 is connected it just spits the ball out and you have to re-cock the lever, tried on 3 different tanks. I know the tanks are good, we tried them on a different gun. i took it apart and didnt see anything blocking. any ides or could i have missed something