NYC cigarette smell - condo legal bill

Hi - My husband and I own an apartment in NYC. There aren't many "young" people in the apartment and many tenants are longtime owners, but perhaps one of the new tenants is a smoker that has a tendency to smoke inside the apartment when it's too cold, too hot, or rainy. We'd made multiple written complaints to the management office, and the office had said he'll think about getting the law firm (one that the condo uses I guess) involved. Happened once more and I said can we take the legal way and send him a letter that way - we did and that legal bill apparently got applied to MY common charge bill the next month. Is this something that I should've known and embraced when I asked for it, or something that I can maybe ask them about and appeal?