Description : User is trying to delete a promotion but is getting an error “This record cannot be deleted because it has dependent records”. One of the reasons is that the promotion record was already used on a transaction like Sales Order or Invoice. To delete the promotion, the promotion code has to be removed from the transaction record first.
Solution
1.Edit the transaction that used the promo code
a. Navigate to Transactions > Sales > Enter Sales Order > List
b.Sales Order: Click Edit
c.Click Items
d.Coupon Code: Remove Coupon Code
e.Click Save
2. Delete the promotion code on the list.
a. Navigate to Lists > Marketing > Promotions
b. Promotion Code: Click Edit
c. Click Actions
d.Click Delete