Citroen C4 i have new citroen lane assist problems.

I travel only short distance in Citroen c4 I have on mobility. On several occasions the lane assist light comes on and seems to want to take over steering. I sometimes struggle to keep steering straight. Yesterday I overtook on motorway then when I was returning to left lane the car was seemingly trying to keep me in middle lane for several seconds frightening really as though for short while you don’t have full control of vehicle. Phoned dealer who told me to turn off lane assist just wandering if anyone else has come across similar fault.