Need new sunroof seal.

Need new sunroof seal. There was rust oround the edge of the sunroof, on the actual roof it self. Took it to get it repeared and need a new seal. Went to BMW Dealer to get a new seal, they asked for the chassie No. and they gave me a different seal.Doesnt look like the one I took off. The one I took off my car was ateched on the roof its self. Not on the Sunroof.And the new one is glue on type. Dont know what to do. Help please!