iPhone 6 email receive problems

Hello, for the lsat 6 months (since I got my iPhone 6) I am havine terrible email issues. Once every 5 to 7 days both my outlook and pop3 iPhone emails stop working. Nothing is downloaded. The "wheel" spins on my email accounts but no mail arrives. Usually, after a while, the email header will download but not the body of the email. If I reset my phone and then press the mail button, it will work - once. I then need to reset the phone again for it to work a second time This happens to both my outlook and pop email. If I wait for 2 or 3 days the problem will clear up on its own. Or, if I delete my mail accounts and reinstall it will work for another 5 to 6 days. During the times that my iPhone email is not working, my iPad Air email (same email accounts) works great - with no issues - ever.

Thanks for your help!