#5.5.0 Smtp Looks Like Spam Or Phish Why Do My Ringtons Fail To Send To My Impulse Razor Prepaid Cell Phone From Myxertones.com?

Why do my ringtons fail to send to my Impulse Razor prepaid cell phone from Myxertones.com? - #5.5.0 smtp looks like spam or phish

Ive tried to send different ringtones, but I receive an email called Delivery Status Notification (Failure)
Action: Failed
Status: 5.5.0
Diagnostic-Code: SMTP 550 SMTP connection

Ideas and suggestions greatly appreciated.

V3m phone models. Verizon Wireless