[RobTux]

I have a 430d 3 litre x drive, 2016 model - mileage at 27,000 fitted with auto box
4 days ago I was maneuvering on a very steep slope. I heard a loud clunk and then it would not engage either forward or reverse gear. I called recovery who turned up 3 hours later. They got into the car and it worked perfectly. I drove it about 100 miles since then trouble free.
Today (whilst not on a steep slope) whilst maneuvering into a parking space it happened again, this time without any loud clunking noise.
Again I left the car for about 3 hours and when I got back in, it worked perfectly .
Has anybody got any suggestions? (apart from taking 3 hour lunch hours every time I leave home!)
Thanks

RobTux

[Eddamoo]

What 'gear' was the car in while it wasn't responding to your input?

I would try and get the car's error codes read, I'm sure there will be something logged.