Once again I'm having problems sending mails due to Zoho being blacklisted:

ERROR CODE :554 - Refused. Your IP address is listed in the RBL at bl.spamcop.net: Blocked - see https://www.spamcop.net/bl.shtml?136.143.188.17

SpamCop confirms Zoho is blacklisted at this moment:

136.143.188.17 listed in bl.spamcop.net (127.0.0.2)

The offending IP is the same that I asked for few days ago and been said that it had been supposedly delisted. But here we are again... Can't this problem be solved in a more permanent way???

This is starting to hurt us, we need to be able to send notifications to our customers in time. Please fix this.