Well first of all, the tag should have a blue or a yellow ticket which tells that it is a LAST ACT item! Secondly, even if there is no such thing, then when the receipt is printed (although the stuff at the rack says its last act or it might displaced because of other customers), at the very end you will see written that "Last act items need to be returned within 30 days of purchase", & finally, the associate always reminds you that it can be returned within so & so time but if they forget, it is YOUR duty to ask them since you are paying YOUR money.. Nevertheless, if any issue, the Managers are ALWAYS available to help you regarding such situations! You can also contact customer service live chat on Macy's.com & they can send u a shipping label for your return!
Go to the store manager and explain your situation. They should have told you, also they are in a position to sell that dress and you are not. I respect Macy's and trust they will do the right thing. All good wishes.
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