BMW headlamps are rubbish when it comes to condensation. My 2014 5 Series that I leased privately had this issue as well as rattling from the Harman Kardon sound system. Funnily enough, the dealership in Kentish Town (which is no longer open) tried gaslighting me with the rattles but not with the condensation. Mechanic sat with me in the car and tried to pretend that he can’t hear a rattle. In the end, I got them to fix both issues to a satisfactory degree.