Blacklisted?

The domains below are rejecting mail from Zoho's servers. I've blanked out the initial part of the email address. How do I get this fixed please?

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###@iafrica.com INVALID_ADDRESS, ERROR_CODE :550, ERROR_CODE :rejected because 135.84.80.216 is in a black list at dnsbl-1.uceprotect.net

IP 135.84.80.216 is UCEPROTECT-Level 1 listed. See

###@mweb.co.za INVALID_ADDRESS, ERROR_CODE :550, ERROR_CODE :rejected because 135.84.80.216 is in a black list at dnsbl-1.uceprotect.net

IP 135.84.80.216 is UCEPROTECT-Level 1 listed. See