Payment process
Here is the general exchange process for a SEPA Direct Debit:

Steps 1, 2 and 3: Exchange of documents
SEPA Direct Debit is based on a SEPA mandate. Your debtors must sign this mandate in order to prove that they consent to the creditor debiting their account. Each mandate is identified by a Unique Mandate Reference that allows to identify the contract to which the SEPA direct debits are attributable.
For each SEPA direct debit, the creditor must send the debtor a pre-notification, 14 calendar days before the direct debit expiry date, to warn him or her about the direct debit.
Steps 4 and 5: Sending messages
The creditor sends the SEPA Direct Debit order to his or her bank. The bank will contact the debtor’s bank in order to proceed to SEPA direct debit.
Steps 6, 7 and 5: Transfer of funds
Funds from the debtor’s bank account are debited and transferred to the creditor’s bank account.