How to fix a reclining loveseat back to the upright position?

I was sitting in the reclining loveseat and attempted to return to the upright position, but the chair wouldn't move. I looked at the other seat next to the broken one, which moves with no problems and couldn't see any difference. what do I look for on the broken side of the recliner to get it back into the up right position? I believe the loveseat is maybe a lazyboy Gavin La-Z time loveseat.