There are a number of reasons this could occur.  Below are some of the reasons.  If these are not relevant, contact support.
  • The credit card information being incorrect. Specifically, if a donor has received a new credit card in the time since making the donation (with a new CVV code) the refund will not process.
  • The credit card expiration date is in the past.
  • Many merchant accounts don't allow refunds after a certain amount of time has passed, usually 60 days or 90 days.

If the above are the cause, refund the donor offline. Then, to remove the transaction from Luminate Online, follow these steps.