Everything now-a-days come with an SN and a store id. Yes, bring your credit card and the statement. You could also say it was a gift. Macy's is usually good about customer care.
Try your credit card statement as well. I used that with Best Buy.
I believe you need the receipt but try it anyway some watches come with a serial number
They might have the receipt on file. If you have the credit card that might work.
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