MPCNC \ SKR PRO V1.1 \ Marlin 2.0 \ TMC 5160 Weird issue

It appeared as missing steps. But the more test I run, it is like a bad request. It only appears on the Z axis. But I move by [G0 Z5] or [G0 Z-5] and some times I get 5 or 2.5. I move 1 and get 10. this makes little sense. Or I try a negative move and getting a positive reaction.

Any thoughts

What speed are you trying to move Z at that moment? Too fast and it’ll act like that.