I am a residential customer of Verizon and also a small business owner. Emails from my business to my verizon.net customers are being returned. Return reason is " Your IP has been blocked because of spam issues or because your ISP indicates that it is dynamically assigned" I have verified with our email host that we are not using dynamic IPs, and our IP is not on any known spam lists. I am looking for a specific reason our emails are being blocked ?