https://www.epo.org/en/node/submitting-deferring-and-revoking-debit-2

How can I (partially) revoke a debit order?

If you deferred payment to a later date, you can revoke your debit order in Central Fee Payment by clicking the Revoke button (in the list of orders in status Pending in the Transactions tab under Deposit account management). Debit orders without a deferred payment date can only be revoked as per point 13.1 ADA, i.e. by submitting a signed written notice of revocation either as an attachment to an email to support@epo.org or via the EPO contact form.