How to Fix a Butt Wink During a Squat

[allnaturalindian]

very helpful video, nicely explained, ty

[russell]

My lower back curves in my squat at the bottom of my squat, the squat is usually a low squat I feel like it might be bad but I keep being told it’s fine and to keep my form the same and that I think to much into form but I would like to know is it bad? Should I change my form or keep it like I’ve been told.