P2098 CEL + Start Stop Issue with hesitation while driving

Whats up guys? I have a 2019 Grand Cherokee Limited 3.6L and been having these issues that the dealership I got it from (bought certified preowned with 20k miles) can't seem to figure out and fix. Heres what's going on; I keep getting a CEL light throwing a P2098 (post catalyst fuel trim system too lean on bank 2) code. Dealership first said it was a "bad batch of gas". I use 89 octane gas and after they told me that I filled up about 2-3 times before the same code was shown again and the "start/stop service soon" message comes up on the dash and my jeep seems to be hesitating or "slipping" when switching gears. Brought it back and they said they checked all O2 sensors and everything pertaining to that code and that there is nothing wrong and the code will come back on a couple times before the CEL stops coming back on. As for the "start/stop service soon" message they said that comes on when the CEL comes on. Brought it back and they said my air filter box was "loose" and that was the problem. The day after I picked it up for the 3rd time, the check engine light came on again. Then my jeep started to stall out and shut off on me when I put it in reverse to back out of my parking space. After 2-3 times of trying to get it going, it finally stopped stalling on me and I was able to make it home (with cel still on currently). I am at a dead end with this dealership that is most likely playing games with me and was looking for some help from you guys. Let me know if you guys having any questions or if you have any diagnosis for me! Thank you for your help in advanced.

Ps. I am not a car guy so bare with me lol

 

This will sour your FCA/Stellantis jeep experience. Might cost you some $ but try another jeep dealer for some resolution that the certifying dealer could not resolve. Maybe the jeep is new enough to have some factory warranty for bumper-to-bumper plus emissions. Try contacting FCA/Stellantis? As a car guy I would be firing a few parts cannon at the problem such as replacing some OEM O2 sensors which won’t be too expensive except when paying someone else to do it.

 

What is Stellantis? Also the dealership said everything came back with normal readings including o2 sensors.