Way off topic but need ideas Patio Chair Fix

[s10blazerman4x4]

Got a new patio set about a month ago. 6 chairs 1 table 2 ottomans etc etc

One of the 6 chairs will not lock. It has 3 positions. Straight up, somewhat reclined and fully reclined. Ive taken it apart and do not see like a rubber stopper in there or anything. When I assembled them they all went together pretty smooth except for the one which had the cross drilled holes. I ordered a replacement from the company but that is on backorder. I have 5 working chairs.

How they work is you lift up the arm rest and push back and it will adjust the position. I can post a picture of the inside of the arm rest if it will help generate ideas on how to fix. When you flip the arm over there are 4 screws holding the one mechanism into the underside of the armrest. I was thinking of just trying to lock it in the upright position so at least its functional.