Citroen c4 grand picasso

[GemB]

I've had my semi automatic Citroen c4 2014 for a little over a year now, and have had nothing but problems with what comes up as a gearbox fault. I've had the clutch and fly wheel replaced which was completely trashed so thought problem over.
The car drives fine (mostly)around town every so often the car will jump out or automatic into N and I have to flick the stick from automatic into N and then back to automatic and it drives fine again. But when on motorway journeys the car will drive ok for moat of it but then will flick into M6 from A6 stay in M6 for a little while and then back to A6 by itself all while flashing gearbox error at me again??
Can anyone help on what the cause of this could be as garages just look at me like I'm a confused woman and tell me I need a new clutch but mines less than a year old???

[Mazzy7126]

Gearbox actuator is failing at a guess.

[GemB]

Oh no! Is that something I can get reconditioned do you know? I was quoted 2500 from Citroen for one of them without fitting.. surely that almost out values my car