Hello! You can try to
- Tweak Physics settings in Project settings (https://www.reddit.com/r/KerbalSpaceProgram/comments/1ruodr/max_physics_deltatime_per_frame_setting/)
- Use CCD mode for capsules collision (Set Use CCD | Unreal Engine Documentation)
- Check collision thickness of floor if you modelling it as plane or landscape (Landscape Collision Guide | Unreal Engine Documentation)