New camera, nube photographer.

In my R50 the autofocus area can be selected and moved around, but can it be locked to the center? I currently have it set to the point focus, so the smallest focus area, but I find that the box that shows where the camera is focusing moves around (no faces involved or vehicles) Usually the focus square jumps up and to the right, and sometime moves around while I am trying to compose the shot. Is there a way to lock it down so it will stay in the center?

Update: I tried several things and lost track of some of them. It seems my focus point is staying put now - it is just off-center but close enough to make me happy.