2016 Nissan NV 2500 HR Rear door will not open

[Silvieus]

My van is fairly full as I moved recently and used the van to move merchandise from my storage unit. Anyway the sliding side door is stuck and will not open because things are laying against it and it has happened quite a few times over the years. Now however not only is the sliding door stuck but now the rear door is stuck as I think a box may be lodged against it and causing it not to open. Other than going through the cab and clearing everything out a task which would take a few hours does anyone have any clues on how to open the rear or side door when an item is lodged against it. Any help appreciated.