Yahoo refuses to recieve email from zoho

Yahoo refuses to recieve email from zoho

I get the following error if I send an email to a yahoo addresd

ResponseCode 421, 4.7.0 [TSS04] Messages from 135.84.80.217 temporarily deferred due to user complaints - 4.16.55.1; see https://help.yahoo.com/kb/postmaster/SLN3434.html]

And I have only send 2 emails to yahoo.
Any ideas how to solve this