Username And Password

I own a computer repair business for over 25yrs,, so just Maybe I might know how to setup my email accounts. Each day 100s of times I get prompted to enter my username and password.. if I hit cancel,, and hit send and receive just 1 second later it works fine.. sometimes I can send and receive 20 times in a row with no issues, but usually within 5 try's I get prompted for my password again.. it happens with my IPhone, my IPAD's, Windows 10 (outlook 2016), thunderbird, and built in windows 10 mail and I see it everyday at my service calls, with my own clients that use cox what is the FIX? Jeff