cox keeps flagging some mail as spam

Having the same problem for the last 2 months.  Several sites, actually.  walkradmin@gmail.com is the main one.  A suggestion was to send to thisisnotspam@cox.net;  That link did not work & still going into spam.  Other sites including my bank and Staples will periodically put their messages into spam.  And, these last two sites are not something a scammer sent.  Now, someone said to check the Spam folder to make sure I haven't marked these sites purposely as spam.  Pls lead me to this link as I cannot find it.  If you look on my account, you will notice I've chatted about this problem about a month ago.

And, no, I will not change my addresses to gmail.com.  I would like to know if this can be fixed on your servers.  If it cannot, let me know so I am aware I need to tolerate this bad situation.

I've been with your Company for over 40 years; and, yes, my Son works for your company for the last 24 years.  Your service throughout the years have been better than good.  I'm hoping that this situation can also be solved.  

Thank you.

Hi Cableguymom, with the message in your spam filter opened, please click the menu hamburger at the top right and mark the email as Not Spam. This helps teach the spam filter what messages you want to keep. You can also click on the sender's display name to add them to your address book. 

Working on your ideas, MichaelJ.  

MichaelJ - as you said" Hi Cableguymom, with the message in your spam filter opened, please click the menu hamburger at the top right and mark the email as Not Spam. This helps teach the spam filter what messages you want to keep".   Didn't work.  

"You can also click on the sender's display name to add them to your address book."    Where is this "address book" located on the Cox Inbox link?