Where it usually breaks
And how to keep it from happening.
- Unknown response treated as success. A request that reached the provider still needs a confirmed outcome before cash is reduced.
- Blind repeated refund. Read the existing effect before sending another request that could duplicate the refund.
- Unrelated reference. An external identifier must match the selected order and action scope before it establishes completion.
- Deleted executed evidence. A correction needs the original outcome available for review and reconciliation.