If there are no available funds in your account and you still need to process a return, you must upload credits to the account.
You can do this via a regular bank transfer using the following bank details:
Beneficiary: RDPTS GmbH
IBAN: DE68 3004 0000 0050 0025 01
BIC: COBADEFFXXX
Bank: Commerzbank
Purpose: XXXXXXXXXX (your account number, which can be found on the dashboard in the seller portal, as shown in the image).