Email routing failed

General Email Routing
#1

Rejected reason:
Unknown error: permanent error (521): 5.3.0 Upstream error, please check https://developers.cloudflare.com/email-routing/postmaster for possible reasons why. CfoJA4eGFJWV

SPF status
pass

DMARC status
pass

DKIM status
neutral

#2

Hi,
Did you get any solution for this error?
Since I am also getting same error with one of my domain.
Please help me out if you have any solution for this.

#3

Not found any solution yet

#4

Does the community tip help? This is what Error 521 is supposed to mean: Community Tip - Fixing Error 521: Web server is down