Hey there @Nekot_The_Brave! Welcome to the community! This is definitely an odd one. It looks like your walking back is fighting over turning or not, or overshooting the turn in a frame and putting it back after. Are you inputting pure -1?
Try disabling your turning for your forward/back movement for a second to see if any other rotations occur during your forward/back movement. It obviously shouldn’t but I’ve seen some weird situations, like characters movement being overridden by Orient to movement input before.
And let me know how it reacts if possible.