Triumph 5255 Cutting Machine - Clamp Bar Stuck in Down Position

Is there any way to manually release the clamp bar on this machine?
The manual does not give much guidance for the safety buttons below the machine, and none of the 3 buttons were successful at releasing the bar.
We are unable to operate the machine because the bar is stuck clamping down a ream of paper.

Any help?

 

Hi sir;

Please test the Switch s7, for release the clamp bar TOp, clean it, tight, and test continuite, and adjust,, and see if contact K4 is Pull in in order to release the clamp to the TOP .