bone snaps back to original position

When I use the gizmo to rotate a bone, and then I get out of the gizmo and just use a straight move, the bone jumps back to the last position I had, What to do?

are you in pose mode, edit mode, or object mode? are you switching between modes? are your pressing the right mouse button to end your move? could be many issues do you have more details? of a blend file to check?