Brushes not working properly and project crashing

I’m an animation student using ToonBoom Harmony 15 and I’ve been having a major issue lately with the Harmony brushes:

I start a project and draw with a special brush (marker, charcoal, soft led etc…). When opening the project the following day the brush display shows a black rectangle instead of the preset and my drawings look bad (as shown in the screenshot).

Even if I try to draw with the pencil tool instead of the brush tool the lines don’t come out right and the harmony crashes.
After looking for ways to fix the problem I ended up needing to go back to and old recovery point, uninstall harmony, restart my computer, reinstall my Graphics driver, reinstall Harmony and restart the computer and only after doing all that the harmony would go back to its proper brush display.
This has happened numerous times (first time in October, then again around January and lately it started happening every few days!).
All this headache takes about 2 hours at the least and the last time it happened (this Tuesday) i had to do it twice because the harmony crashed after the first time and my whole project was erased.

I own an:
HP NoteBook Pro with 16 GB RAM
Windows 10
graphics card: NVIDIA Gforce 930MX

I have no idea why this keeps happening and this is a big problem since I work on animation projects for the academy on a daily basis…

Please help if anyone had the same issue and knows how to fix it for good,

Thanks in advance,