Why Was The Shipment I Received Not The Order That Was Originally Placed?

Apparently someone made a mistake but you need to act rapidly to return the item (including all packaging) within 90 days to receive credit.

Rather than mail the item back to Target, you can probably just return it to a Target store. Just check the packing slip to determine if the beer mugs are eligible. Assuming they are, simply gather up everything that was sent to you including your packing slip and credit card and take it to Customer Service for a return credit. Make sure that you have your photo ID as well.

I would suggest that in this case, you go to the online catalogue and print the item page with the photo just to make your return move more rapidly.

You can always use the store locator to find the Target store most convenient for your return.