I recently had some work done on my mower. We put the deck back on but now it is cutting extremely low and the mower is getting hung up on every little dip in the yard. I need to adjust it myself but am not sure how to work the mechanism. It is a circle with numbers on each pin hole. Should I move them to the highest number? Also, there is one on each side, only the left seems to be doing anything. Do they both need moved?