Hi all, just an update in case you are interested - i took the car to the same dealership, and they've identified an issue with the Body Control Module, so they`ll be replacing it and reprogramming everything. They managed to replicate the issue by turning the heat full blast and leaving it on for a while. Hopefully replacing the BCM will resolve the issue. A bit disappointed to be honest that a 2017 car with 30k miles, which was babied by both me and the original owner, requires such an expensive repair. I am not sure what could have caused it, or if BCM's are something that are prone to breakage, but that's where we are at the moment. Cheers and thanks everyone who read/commented!