NHTSA Complaint #11523536 — 2021 TESLA MODEL Y

Driving I-80 on May 9 between 2 - 4 pm going approx 70mph using autopilot. Sudden, unexpected, rapid deceleration causing back seat contents (suitcases & my dog) to fly forward. Nothing in front of me, no visual obstruction, weather clear and sunny. Luckily no one behind me. It felt like I had slammed on the brakes. I did get off highway shortly after to get dog out of where he lodged in back seat.Tesla rep via text messaging said I caused this by tapping accelerator & no need for inspection, but I do not recall doing that. I did receive a message/warning around the approx time I think this occurred stating “Driving visualization temporarily degraded” (I have screenshot.) They did send me the spreadsheet data of that day but I can’t decipher it.