550 5.7.1 2607:f8b0:4864:20::636 isn't allowed to send email for [email protected]

What is the name of the domain?

What is the issue you’re encountering

cannot receive email sent from gmail server

Cloudflare doesn’t provide outbound (sending) email service. And the IPv6 address 2607:f8b0:4864:20::636 belongs to Google, not Cloudflare.

So I’m not sure how this relates to Cloudflare.

If you can provide a bit more detail of the scenario that’s leading to this error message and share your domain on Cloudflare that’s involved in this, we might be able to advice you on what to do.

i have setup email routing eg.
[email protected] → (forwarded to) [email protected]

someone using gmail to send to [email protected] but received this undelivery email alert.