I see account NL04ADYB2017400157 on my statement.
Postex sends messages with payment requests on behalf of insurers, housing associations and local authorities. Postex uses Adyen’s payment services for this, they process your payment. That is why you see an Adyen bank account number NL04ADYB2017400157 when making the payment.
See also https://www.adyen.com/why-do-i-see-adyen-on-my-bank-statement.
If you have any questions about this, please contact the organization from which you received the message.