AOL Mail Fetch error showing on iPhone?
Your phone's default settings for fetching new emails are based on the settings available through your email provider. If your provider doesn't support Push notifications (where emails are sent to your phone as they arrive, in real time), it will automatically enable Fetch (where your phone retrieves emails regularly at preset times).
These settings impact how your phone receives emails. To adjust them:
Tap "Passwords and Accounts."
Scroll to the bottom and hit "Fetch New Data."
There, you'll be able to see the incoming and outgoing mail servers. Compare these to the recommended settings via Apple's Mail Settings Lookup widget.
TO know more - https://www.theemailhelpline.com/aol-com-email-login/