I made a big mistake when I first entered in cryptocurrencies because I took participated in a campaign MB8 miltibuy project managed by Yahoo sir . But I transferred all my coin on whitebit exchange but unfortunately my all coins vained due to exchange delisting.
Have you not contacted with them. I think the coin is delisted but they are still with them in their account. You can trace them with the help of developers and tell the exchange that my coins are with you in that address. They will help you.