2015 hyundai elantra

I went to pull out of my driveway a couple weeks ago and after I reversed out into the road, the car would not move forward once I put it in drive. I backed the car into the driveway and had a mechanic friend come over. He unplugged what I have pictured above (idk what it's called,sorry). The check engine light was not on. He plugged it back in and also used his scanner to check for codes. Magically the car drove forward after plugging it back in.

I drove the car with no issue for a couple of days. Then it didn't want to drive forward. So he suggested I unplug and plug back in like he did and after restarting the car, the car drove forward again. Not a fix but a bandaid. I did this a few times over the course of a week.

I chose another mechanic to come out after reading another redditors story and saw that a bad wheel speed sensor was the culprit. It turns out, I did have a bad wheel speed sensor. The mechanic replaced it and the car was driving great again! I was so thrilled!

Until the next morning, and then it didn't want to go forward again. The fluid level is good. No check engine light.

The new mechanic wants to replace the neutral safety switch. I have been reading a lot and I'm not sure that sounds right.

So i figured I would post here and see if anyone has any suggestions.