Henry HVR 200 - How can I fix red switch?

It fell down the stairs, and the red switch cover moved from its proper position. I have taken it apart and it I just can't get the red switch cover back in the right position. Without it the switch works fine, ie. pushing the switch push rod to make it go on and off, but when I put the red switch cover on it seems unable to move up and down sufficiently to switch the cleaner off. Any help would be appreciated. Thank you.