DF 54 grind size …

Hi everyone! I purchased the DF 54 a while back to go with my bambino. I am still a beginner, but know (mainly because of this forum) to always “grind finer” 😂. So, after reading that many of you were grinding from 0-15, I tried to pull a shot everywhere in between those settings- probably 10 times but the espresso would never come out. I found that the sweet spot for my machine is between 20-25, but I’m wondering if there’s a way I can fix that? I guess it doesn’t matter too much if that’s what works for me, but I’m wondering if anyone else has experience this issue and what they’ve done to troubleshoot it, or if it really doesn’t matter. TIA