Missing registration code

[CallMeMarc]

The retailer said to contact Square and that they wouldn't do a return or refund

[Hokulol]

If they won't do a refund, call your credit card company, assuming you bought it on a credit card. Ask to have a chargeback done, after explaining the situation. There is nothing either square or your retailer can do to prevent a chargeback from happening. Contact square is... well... not going to happen this month. After they refund it buy it again from somewhere else. My best advice.

Good luck