On one of my drawings I have injected an issue. When I want to change the Ref. point, I push the " ~ " and then position the curser and do a "Left mouse click once". X and Y then are reset to " 0 ". For some reason, I've done something to not allow the X and Y to reset to "0". It's only on one of my drawings, all the other drawings, it works fine. Any comments on how I might resolve this issue?