Transmission Gear Slipping problems of the 2010 Nissan Maxima

I've had my car for a little over a year and only one owner before me, it has been maintained well. My car has been making a noise for months now so I finally took it to a dealership (on August 3, 2019) and was told nothing was wrong. Not even a week later it broke down almost 2 hours from my house. Other than the knocking noise (which including a popping noise), uneven tire wear (had a blow out on 65 3 hours from home), it started not accelerating when I was at a stop sign or light. It still runs, but I've spent over $500 within a months time trying to receive answers and haven't yet. I see recalls for other years as in the suspension/strut insulator cracking. Also, I've seen other complaints about transmissions slipping and Nissan not wanting to fix them. I am now expecting my first child and have no form of transportation due to Nissan and their dealerships not knowing basic car knowledge nor wanting their customers safe and satisfied.

While driving the car to southern cal, the service engine soon light came on. The car would not go above 2000 rpms periodically. I parked the car for 1 - 2 hrs and it seemed to start working again. Once home, I headed to the mechanic the next day and the transmission slipped completely. I should have stopped and called Nissan on the highway because once I made it home the odometer was above 120,000.