What happens if the Retail Express Voucher has insufficient Credit Available?
Where an order uses a voucher that has been spent in Retail Express and NOT updated in BigCommerce (This should not be possible) but could occur where the customer uses a voucher in REX POS, and then tries to redeem it online before the coupon sync has marked it as used/expired.
There will be an incorrect value in the remaining balance for a coupon that was used in the order, the order will still get processed in Retail Express without failure.
However,
1) the order status in Rex will be marked as "awaiting payment"
2) A balance due equal to the difference in amount between Rex and BigCommerce will remain owing.
For example
Coupon used P64B2Y29, amount in rex: $10, amount in eCommerce:$100
