Relay in RNBL
Hey there,
We are currently facing an issue where our transactional emails are being blocked by some companies.
DKIM and SPF records have been set up and verified. The domain itself was also checked on senderscore.org, and no issues were found.
Additionally, using https://mxtoolbox.com/SuperTool.aspx?action=spf%3ameincoach.de&run=toolpage, no problems were detected either.
Overall, everything seems to be in order.
The emails are being sent via an SMTP server (mailbox.org).
The only issue we could identify is the following:
RCVD_IN_RP_RNBL - Relay in RNBL, https://senderscore.org/blocklistlookup/
However, I couldn’t find any relevant information about this in the forum.
Does anyone have an idea why this might be happening? Considering the relay is mailbox.org, why would it be listed on a blocklist?
The same problem 
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