Go back to ST entry, click on "Search our sweep" feature, type in "Miller Lite" and see if your t-shirt is listed as one of the prizes in any of those sweeps.
If you received an email that you won, email should specify how to claim prize.
If you purchased an item and received a winning notice, it should also specify how to claim prize.
Hope this helps. If not, come back, post again, and someone will try to help you.
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