"transient error (421): 4.7.0" when forwarding emails to Gmail

Same here. And happening with 9 different domains. It seems that a lot of us are experiencing issues when using the Email Routing feature from Cloudflare with a free Gmail account. I’ve implemented all good practices (SPF, DKIM, DMARC, MTA-STS, TLS-RPT records…) and still facing the error (421): 4.7.0.

Incoming emails are rejected due to sender’s (mine, because of the forwarding) domain low reputation. As I can see many of us are experiencing this issue, I’d say Google doesn’t like Cloudflare’s IP or something like that. Because, despite it being my domain the sender, it is CF’s server the one forwarding my incoming emails to my free Gmail account.

Funny thing is that not all my incoming emails are rejected, just some of them, what is kind of puzzling, right?

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