Draggable widget (UE 5.6.1)

I am trying to create a draggable widget. The first time I grab my widget by a button, it snaps to the top left corner of the screen, after that it functions normally.

If I set position in event construct, the widget no longer snaps to the corner, but it also spawns slightly off center, which bugs me a lot.

Please help me resolve either of those issues.