I was sculpting my first ever object in blender. It was working fine no issues, then i switched between object & edit modes and came back to sculpt mode when applied my brushes those did not affected my mesh. I checked all settings again if everything is correct like Dyntopo, Start and end clipping, symmetry, Brush stroke, Brush Radius everything was selected and enabled. I surfed through internet for to find out people facing same issue to solve my problem. but could not. Maybe, i am still wrong at something. If you guys check my file and see through that would be the most help for me today.
I don't do sculpting, so can't help much... But here's a video where it explains how to configure the hot keys of each of your brushes so they work correctly: https://youtu.be/eGuDCgU_4os
And this is an old video that solves some common problems of sculpting: https://youtu.be/DAdYQ4xpNo0
If nothing of the above helps, then save your project file, and try uninstalling and reinstalling blender again, or use a portable (zip) version of blender... Then open your file and check if the brushes are working again