Changing between Fixed off set and Pre-side off set

I don't know if it's just me but the Fixed off set and Pre-side off set won't change at all. I'd prefer the Pre-side off set but as I was playing a game I felt like I was on the fixed off set. When I changed between both of them it only stayed on the fixed offset so when you change it to the pre-side off set, it won't change at all.