Chrysler Grand Voyager thrird row powwer seat jammed

Unstowed the seat. but there was a box whick blocked the front left leg of the seat from coming down.

Now it's folded back underneath the seat and no mater which button we press to change seat positon it either moves more closed and stops or moves slightly back and stops.

Is there any way to manualy reverse the seat to free it.

thanks

John