Proper positioning of the Top Cap #52 is important for the seatpost to function correctly. It must not be too tight or too loose.
Put the seatpost in the up postition
Push straight down on the seat. If the top cap is too loose, you will have some play up/down and hear a clicking noise.
If there is play, slowly tighten the Top Cap until there is just a small small amount of play. If you tighte this too much, the post will not engage properly in the UP position, or could get stuck in the UP position, or fall from the UP position while riding
Put th rubber boot back down over the top cap and test the post to see if it is functioning properly.