What are you reading the codes with? Is it a general scan tool? I ask because the P code is standard for “powertrain” and the #1 there indicates that it’s a manufacturer specific code. This is why I ask, a code reader that will read the BMW specific codes should have given you 2 more numbers instead, to indicate the code. AutoZone and the like can read general DTC’s (diagnostic trouble codes) but not our BMW ones. It sucks, totally, but you may need to take it to a shop that specializes in BMW/MINI to get them read, unless you know someone who has a scan tool with the correct software.
Getting the full codes is the first step to getting help to fix it.
I hope this helps

INPA seems like it would be over my head, lol.... I stick with my Schwaben scan tool, it’s easy for the easily confused like me, ha ha.
good luck and keep us updated on what you find out. I’m following with interest. Without know any more than before, I don’t really even have anything to suggest for a starting point. Are you experiencing any other symptoms or things that maybe seem related or is the code popping up under certain conditions like heavy engine load or anything like that?