2015 Vauxhall Insignia electric chair problem

First post, whoop.

Recently bought a 2015 siggy, I have a problem with the electric seat in that it moves quite often of its own accord, even whilst driving. They are very small movements and dont as yet interfere with the same operating of the car but things like this don't normally get better.

I can't find in the manual how to clear the stored memory positions as I was told by the seller (perrys huddersfield) that this was the reason.

Can anyone offer any insight into why this is happening and how I can resolve it?

thanks.

Jack