Solo Mode Crashing

Hey, I’m using Toonboom Harmony 20 and about a few days ago, my file just started crashing whenever I entered into solo mode. Doesn’t matter if I solo one layer or ten layers. Is it a bug or is there some other issue I may not be aware of? I tried opening other files to see if I could go into solo mode without toonboom harmony crashing and it seems that I can. Any help on this issue would be much appreciated. Thanks!