Postgrey Blocking most Mimecast / O365

[NoCauseza]

Morning,

Since about the 1st of October we have been getting rejections from Postgrey.

4.2.0 ppl@nayarit.be: Recipient address rejected: Greylisted for 300 seconds or its been rejected.

This is only with sending to services using postgrey,

Can anyone help?

[schweikert]

What is the hostname that you saw in the logs? Sorry for the very late response...