Build issue or skill issue?

I see people posting 40k+ points on here and I’m struggling to hit 20k on UCC 😭 Haru’s only M0 bc I lost my 50/50 to M1 Rina on his banner. I see a lot of people on this subreddit using Nicole. Would M6 Nicole be better than M1 Rina? I don’t have Qingyi. Are my disks alright, or do I need to pull for different ones? Or do I just suck? Any tips would be greatly appreciated!