Microsoft Time and Date Picker Control SP6 acting up

I need some sort of Date picker for the sheet that I'm working on, I've been using Microsoft Time and Date Picker as an ActiveX control but today It stopped working properly. It has moved by itself to cell A1 and won't move, I can't set another Link cell because "Can't set value to NULL when CheckBox porperty = FALSE.
I was wondering if there is a quick workaround or maybe better solutions.

It will do, thanks !