cl203 foldingg seats

Hi, I have just bought a 2019 c220 AMG line estate and my rear folding seats don’t seem to fold. The seat behind the drivers seat Folds no problem when I hit the switch in the boot,(electronic release) but the rear passenger side wont release when the switch is hit. Seat belts are all out...

My front seats (that fold and jump forward) get stuck in the lock position and takes some grief to unlock them. I am assuming a cable is involved from the latch at the shoulder point, but is there any way to adjust if there is slack in the cable? Cheers all.