HELP: 2009 E82 Troubleshooting O2 Sensor Fault Codes

[SDS135]

Hey guys,

Desperately looking for some help here. I recently maintenance done on my 2009 135i 6MT (oil pan gasket replaced). The day I got the car back I got a check engine light while idling. Pulled the codes, they were all Lamda O2 Sensor related (Picture 1 - picture with more codes), took it back to the mechanic, he said he had to unplug them when doing the oil pan gasket and that maybe he put too much grease when he reconnected. He cleaned the connectors, replaced the gaskets, reconnected, I went for a drive (steady speed not a lot of accelerating). No codes came that night and then the next morning i got the check engine light again. Cleared it and now it happened again (Picture 2 - picture with less codes).

Need some advise to understand which sensor may be giving me issues, don't want to replace all if I don't have it. I want to understand what the codes from Picture 2 mean because they are the ones I just got and hopefully the issue. I haven't had a lot of luck finding much on these codes unfortunately.

It's a little suspicious that it happened the day I got the car back but what can I say.

Appreciate all the help!!

[HawkeyeGeoff]

Have you checked to make sure he plugged them into the right ports on the downpipes?