If you have accidentally made a direct payment from your online internet bank to our payment provider "Trustly" using an old reference number (meaning the transaction was not done via our website), then you need to contact "Trustly" personally to request the money to be returned.
You can do this here - https://www.trustly.com/support/contact
Please fill out their form in English language and add the receipt as a reference so they know which payment to look for.