Hotmail is blocking the zoho servers

I dont know if somehow zoho got on a blacklist, but in the last 3 weeks the amount of emails not delivered or outright blocks has increased by at least 10%. Starting 2 weeks ago hotmail has just plain out blocked zoho. Can you guys do something? Obviously this is a huge problem. I'm having to resend so many emails or set up direct downloads.

ERROR_CODE :550, ERROR_CODE :5.7.1 Unfortunately, messages from [136.143.188.96] weren't sent. Please contact your Internet service provider since part of their network is on our block list (S3150). You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors. [VE1EUR03FT033.eop-EUR03.prod.protection.outlook.com]

Reporting-MTA: dns; mx.zohomail.com

Arrival-Date: Tue, 17 Dec 2019 15:28:31 -0600

Original-Recipient: rfc822; "xxxxxx" <xxxxnameremovedforprivacy@hotmail.com>

Final-Recipient: rfc822; xxxxnameremovedforprivacy@hotmail.com

Status: 550

Action: failed

Last-Attempt-Date: 17 Dec 2019 21:28:41 GMT

Diagnostic-Code: xxxxnameremovedforprivacy@hotmail.com, ERROR_CODE :550, ERROR_CODE :5.7.1 Unfortunately, messages from [136.143.188.96] weren't sent. Please contact your Internet service provider since part of their network is on our block list (S3150). You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors. [VE1EUR03FT033.eop-EUR03.prod.protection.outlook.com]

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