I can't access to IPV4 websites after moving to Cox from Comcast with my Arris SB7580 modem

I recently switched from Comcast to Cox and my working modem is now no longer working with Cox, I can access to IPv6 websites but no IPv4 websites.  I had this issue with Comcast when I bought the Arris SB7580 modem but they were able fix the problem.  I need help from Cox technical folks because the tech guy on the phone were not able to fix the issue.