Drivers Seat Positioning - Changes every time the vehicle is turned off

I just received a 2019 E450 Coupe AWD two days ago. It was shipped across the USA from NY to CA. The very first thing I did with the car was to set the memory for my seat settings. Every single time I turn off the car the drivers seat returns to some contorted position, fit for a Hobbit! WTH? I'm 6ft tall, just shy of 300# (I lift weights every day) and cannot deal with being squeezed into a skrunched up seating position! Can someone share how I change the settings so my seat STAYS in memory position #1? I'm literally amazed that there is even a setting to CHANGE the last used seating position to something surely unwanted, every time the vehice is shut off. Thank you!