audi a3 8P - AIRBAG indicator / 2 plugs from the seat, 1 plug from the car

Hello,
I gave it away, I left the car at the mechanic, during the repair he noticed that the pillows are stapled so that no lights were on.
when connected to a computer, two errors pop up: right passenger side airbag error and tensioner error. 2 yellow plugs come out of the chair, and I only have one plug from the floor. after joining, only the pillow problem disappears. The driver's seat has only one cable with a yellow plug. Is it possible that the chair comes from a different model? And why there is no 1 plug? Is the solution quite different?
please give me a hint

You have the tensioner in the belt winding mechanism, so if you only have this error, look under the B-pillar housing.

I took apart all the plastics today and everything is ok.
and the other chair cable is kind of directed towards the handbrake. I searched everything and I still don't know where to plug this 2 plug. this armchair makes me wonder. is it possible that it's his fault?