All of the emails we sent to our clients have landed in the spam folder recently.

 
I checked the IP address (31.186.226.225) of the mail server in the UK and it turned out it was listed on the 8 blacklists.

My communication with clients is not possible because our emails are landing in the spam folder and me and my team need to call our clients to confirm if they have received our emails.

This issue seriously cost my business damage. I had reached out before to Zoho's support on the general email address (support@zoho.com) but didn't get any reply from there, so i started this topic.

Waiting for the update.