Hi, I've got a 2017 B250E which I've had now for almost 2 years. Mileage is only 14600 and on Saturday 29th May 2021 I pulled up at relatives home and put car into reverse intending to reverse it into drive. On pressing the accelerator pedal it just started to jerk backwards a few inches at a time. The same thing happened on trying to go forward..rang Mercedes and rac came out but had no idea what was wrong so they called the tow truck. It's now in storage waiting to go to Mercedes dealer. Car is 3 years and 10 months old. Does anyone know if it's in warranty or not and have any idea what is wrong. Tow truck had to put plastic ramps under all 4 wheels as none would rotate so it could slide onto flatbed. Any information would be appreciated. Thanks.