cannot access email on cox.com with firefox

The last few days I cannot access my email with Firefox. I can if I use Chrome. I am going directly to cox.com (also tried cox.net)

I get the message:

Unable to connect to mail server. Possible reasons: The mail server is (temporarily) down or there are network connection problems. Please try again in a few minutes.

What's up? I'm using Windows 10, Firefox 80.0.1 64 bit. I have not changed any settings or passwords

Thanks