Rear Split seats loose at bottom - help fixing??

[SimAudi]

I've just bought my first Audi and have discovered the rear split seats knock on the pivot points at the bottom (Missed it on the test drive!) pushing back the upholstery seems to show that the plastic spacers aren't fully in the brackets at the base .

Can anyone give me an idea of how to fix this? Or have any idea how I can remove the rear seats to have a go at it?

Thanks!