Missing Refund, Actinic Payments

[parklifeclothes]

Having issued a refund some time ago directly through the Actinic Payments system the recipent is claiming not to have received any refund from us. We have transaction numbers and it shows as being settled our end but they are still insisting it has not got there, if it hasn't, where is it? and on whom does the onus lie?
We have already sent actinic payment screenshots showing the full details, inc. transaction nad settlement numbers but her bank is saying these are irrelevant as they are from our internal IT system.

Any idea's??

[parklifeclothes]

Update..

Having spoken to BMS it seems that as the sales on that day came to the same as the refund, someone/something decided that neither needed processing so our sales for that day have not been charged and our refund has not been paid so it would seem we now have to chae Actinic Payments/Credit Call...great!!