I purchased a 328xi drive. I purchased along with...

I purchased a 328xi drive. I purchased along with the car the window tint option. the window tint was done from another place. (My wife went somewhere else and not the dealer, she didnt remember I purchased it through the dealer. I usually dont do that) However, for months I have been asking to be reimbursed for it. Since October of 2016
Apparently they cannot afford to return it.
Customer service is a gutter ball