Halo Reach Match making issues.

Okay, I recently bought an xbox live 1 month gold membership and I am sure I did everything right so I went on Halo Reach and It says I need to be an Xbox live gold member blah, blah, blah and so I tried black ops, Modern Warfare 2 and Halo 3 and they all worked but it was just Halo Reach that wasn’t working. I even tried adding another 1 month membership but it still doesnt work.