Dead Battery

[Paul93]

Tried to open my van earlier as normal and nothing.
Assuming it’s a flat battery, I then Opened drivers door manually but can’t seem to get passenger door open to reach bonnet handle and also can’t open side or rear doors.

The van is a 21plate. Only used every second day, also can’t understand why I would have a flat battery. Had an old mk7 before so don’t know much about the newer vans.

Any help appreciated