BMW 730d 2005 automatic

[Davyauto]

Hi getting trouble with the transmission on my 730d, While driving car over slight bump car seemed to select neutral and now it will not allow me to select drive or reverse. Brought it in to my local garage, they put the car on lift and they moved the gear selector fork on the side of the gearbox slightly and they got the gears back. Left garage and drove for about 5 miles hit another bump on the road and it done the exact same again.

Any ideas on what this is or how to fix it would be great, without having to go to my main dealer??

[SebringMan]

Where exactly are you in the country? I'm happy to read the codes if you are in Warwickshire.