They refused to show my score on the leaderboard a while ago, since I am untitled and got a 50. I am in the process of sorting it out with chess.com support to prove I am legitimate.
I'm not sure why your scores aren't showing up, but if it continues to happen I would email support@chess.com
I just got a score of 37 and then afterward 40, does anyone have an inkling as to why they aren't showing up on the leaderboard?