Help needed

[Detox1000]

I own a GLC 300d 2021 , 5000 miles. Car was recalled for issue with heating problem ( which I don’t believe) car was booked in on the 3/2/2022.The day before I was driving home 7.30 pm on M25 pouring down with rain. Pulled off the motorway to collect daughter which took no more than 5 mins as I pulled away car made a jolt then completely shut down .. Had no steering , brakes, power, gears .. every warning light flashing .. Car rolled down the road crossed onto the other side of the rd ( lucky nothing was coming) car stopped by the side of the road . Alarm was going off mood lights changing colours . RAC arrived to check car and it stowed 47 faults and 21 unknown faults. The car would not start and I could not lock .. car was taken on back of truck to Mercedes garage , they have had car for 11 days and still not fixed . There have now agreed that if this had happed 5 mins earlier on motorway we would’ve been looking at fatalities!! I have refused to drive this car again as my daughter is terrified of getting back in it again .. And Mercedes can’t guarantee it would never happen again .. so angry with them !