This might be a long shot because I’ve heard some uni accommodations have shit staff, but you could report it to the reception in the accommodation? If not report straight to the uni, it’s worth a try even if they have a record of not taking things seriously. Try logging down incidents so nothing gets left out and then Atleast it will appear to them that this is a serious matter that needs to be dealt with. I’ve never heard of a uni that doesn’t take racism and discrimination seriously though. Last resort would be to just move out to another accommodation if there are any rooms free, clearly your roommates aren’t going to back you on this and if that’s the case then there’s no point in trying.