this Issue can be closed as it was due to this one
https://feedback.dayz.com/view.php?id=4955

@LeAlexGrey:
no fix so far but i found a workaround (for the affected player)
because i had the same problem when trying to collect stuff for my mates with several bags.

1. find a server and favorite it (good would be one that restarts often on purpose, because the desync will stay on the server until the next restart).

2. connect to it, search a calm place where u can login / out often without being disturbed

3. open your inv and lay down your first "sparebag" which contains the rest of the bags and disconnect (if you stay it won't refresh or takes ages to do so)

4. connect again and you should see the bag laying there...then pull the next bag out of the laying bag and disconnect again and do as often as there are bags inside bags

5. take the stuff in your mainbag that you rly need and leave the rest behind.

(or get some guys over there to pick the rest up for themselves.

IMPORTANT NOTICE: you also won't see that you dragged something to your inv until you reconnected, so don't wonder about it