Mail server's hoster blocked by uceprotectip3 - unable to send mail to Email Forwarded domains

My mail server at mail.novoline.wtf is not able to send email to domains with Email Forwarding enabled.
I’m getting the following error:

<[email protected]>: host amir.mx.cloudflare.net[162.159.205.12] said: 554
    207.180.208.166 found on one or more DNSBLs (uceprotectip3). Refer to
    https://developers.cloudflare.com/email-routing/postmaster/#spam-and-abusive-traffic
    for more information.  (in reply to RCPT TO command)

Upon investigating the blacklist, it seems that UCEProtect has blocked the hoster of the mail server (AS51167 - Contabo). To clarify, every other anti-abuse service and UCEProtect itself isn’t flagging the mail server’s IP.

I think such blacklist is too broad and will cause a lot of false-positives. Personally, I think you should exclude uceprotectip3 - ASN block, from the filters.

That ASN looks pretty hot right now, spam-wise:

It’s also an ASN I’ve personally blocked due to constant malicious probing of many of my websites.

As a personal note, running your own mail server is going to cause you a lot of heartache because of IP address reputation. Especially when it’s on a VPS service with lots of abusive users.

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