I discovered something about my Mini Advance this morning -- I did not know there were teeny-tiny little vent holes on the bottom of the clear plastic cover. I was concerned because my eggs are peeping and starting to pip, and my humidity was dropping. I happened to see the little holes, took a round toothpick and broke it in half, and shoved a half in each hole. My humidity has come up 5% to around 65%-66%.
So, there is a way to raise the humidity without removing the lid and adding water -- something I really don't want to do at this point in lockdown!!!!!
Hope this helps someone else out there that might be having the same problem.