Seat knob not adjusting

[Dave1007]

Hi
Just bought new to me Motorhome on a Peugeot boxer 2007.
Trying to adjust the seats but the knob to turn to relax the back part of the seat won't budge.
Anyone got any ideas on how to rectify this?
Thanks in advance.

 

[JTQ]

Leave and forget about it till after Christmas when your local Peugeot commercial main or "indy" workshop is open.