New member. Sliding door and dash light issue

[duckedupbunny]

Hi I was hoping that someone could help me.
The sliding door on my highway Star closes fine but does rattle and can be rather loud and annoying when traveling at any reasonable speed. Any ideas on how to fix this? Or tighten up the door? Only extra info I can give is that whilst driving, if someone pushes against the door the rattling stops even though the door does seem to be closed OK.

Connected issue: the dash light for the doors also stays on and flashes on and off when door rattles. Maybe door is not actually fully closed but I can't see how this could be as it looks fine? (Confused face lol)

Any help would be great!

Thanks
Kerry