Symptoms
WorldPay refunds fail due to timeout on PBA-E side despite they are completed successfully on the processing Center.
Cause
PBA-E receives REFUNDED_BY_MERCHANT callback from WorldPay but it only expecting REFUNDED callback.
Bug #PBA-57401 was created for the issue.
Resolution
The issue is fixed in PBA-E 5.5.7. Please upgrade to the latest version of PBA-E.