Is it possible to forget how to do sex?

[Cream of Caulk]

I do sex all the time with my husband but we only do it one way when he pushes me face down in the bed. Well today he said sit on his lap and I didn't know what to do, I told him. I forgot how to do this, then he flipped me over and did it how he usually does. I've been spoiled with sex because I don't have to do anything, not even move, he tells me don't move. But now when I sit on it I don't move or know what to do, it was kinda surprising I forget how to sex properly, even when we do it all the time.