Domain name of a foreign brand.

I have a 20-year domain name of a foreign brand (currently not registered in the US) that was used to sell imported items with the product of that brand in the US. UU This foreign brand probably has a trademark in its own country but not a registered trademark of the US. UU They export their products and there are several importers in the United States and a variety of retailers. I took the domain a long time ago and redirected that domain to a Provider section of my website that sells your product. One of the importers of this brand is trying to eliminate control and claims that it represents the foreign country that I suspect is not true. He claims that he has filed a claim for an ICANN domain dispute. So I wonder what my options are in this topic. I am not using the domain of "bad faith" but to sell the real product of the foriegn brand.