Applied discount code availability after refund

Scenario:

Type and method- Amount off order

  • Code

Details- For Online Store

  • $10.00 off entire order
  • No minimum purchase requirement
  • For 1 specific customer
  • One use per customer
  • Can’t combine with other discounts
  • Active from Jun 20

This customer use this discount on an order and paid for it but the order has been cancelled due to insufficient credit or the customer cancelled themselves
Will the discount code be set as “Used” and unavailable to be used again or they can re-apply this code?

In your admin discounts page, you should be able to see the number of times a discount was used in the “Used” column. If it’s 0, then Shopify hasn’t associated the discount code with any order. If it’s 1 or higher, then you might just have to create a new discount code for the customer in question.