Firstly, WELCOME TO FT ^

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I have never asked for a status match so I cant share any experience. However, what I do know is UA and most other airlines, hotels ONLY allow you ONE status match over your lifetime. So I guess that could be why you were denied, if you have already had one status match on UA.
Did you ask them WHY they declined it? Perhaps its worth asking that question.
Good luck. Hope it works out somehow.
Failing that, UA have just announced a long FALL DEQM promo (see the huge thread here on this board) so perhaps a few well placed flights might get you the status you are hoping for. I guess that with all the DEQM promo's we are seeing this year, UA might feel that they dont need to do status matches. There was also a FAST TRACK promo earlier this year, but I believe that was targeted, (also a thread on this board, just type in fast track promo)

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