HELP! need to get into mercedes e class boot

Try the button to release the lock and have someone pull up on the lid . If that don't work there should be a button that looks like a door lock pull around the top of the seat around the head rest. Try either push it down or pull up on the button and the seat back should release if that don't work you'll have to take the back seat out the old fashioned way. Just remember to take the seat bottom out first and check at the bottom of the seat back there are bolts there also.