I have now sorted to car. After being told it was going to cost thousands and that I need a new gear box, it was just the mechatronic unit.
I removed this myself, sent it to be repaired for £250+ VAT and then refitted myself. Also replaced gearbox oil and filter myself at the cost of £60.
This solved the problem and 3 weeks later still going strong! Just goes to show garages just tell you any old ********