I have a gla250 2015 that I recently purchased. It’s automatic but when it’s downshifting from 3rd to 2nd it jerks, a lot sometimes. I took it to the dealership, it’s still under warranty we took it for a test drive and he said everything seemed normal. They did some diagnostics and told me everything was fine. I took it home and the problem was still happening, I know it’s not normal because a friend of mine has a gla250 herself which she let me drove and hers does not jerk the slightest. Also, the auto start stop works pretty much whenever it wants, when I had picked up my car from service it was working but the next day it wasn’t again. Any suggestions on what I should do? I have another appointment at Mercedes next week for the same issue.