IP address marked as spam

IP address marked as spam

I have received notices from both google and microsoft that mail from my ip address is being temporarily rejected due to the high volume of unsolicited mail. My ip address is on none of the RBL servers. My emails to users of gmail and outlook have been limited and mostly responses or a few new mails, but in any instance very few and only with known individuals. What may be the problem and the solution?

Thanks