Why was my customer refunded even though the order was delivered and completed? how am I protected as a seller?

Let me help with your refund, Tacocity.

There is a possibility that your customer disputed the charge, that's why it's refunded. A Chargeback is when a transaction you've processed conveys a dispute, and the money goes back to the payer. QuickBooks Online works hard to investigate chargebacks and to assist our merchants in providing the correct information for any dispute.

I'd like to share this article so that you can check how to Handle chargeback and retrieval requests for QuickBooks Payments.

 All remedies to a chargeback must comply with the Card Association Rules. You can also check this article to know more about How Intuit is backing you with chargebacks. 

However, I can suggest if you're looking for a chargeback protection. You can apply and Sign up for Payments Dispute Protection. 

Moreover, I'd love to share these articles that can help you manage your payments in the future: 

• Handle a customer credit or overpayment in QuickBooks Online
• Void or refund customer payments in QuickBooks Online
• Find out when QuickBooks Payments deposits customer payments

I'll be here if you still have any questions about your refunds. Have a great day, and take care.