Is your AOL Mail not working on the iPhone? If yes, you don't need to worry as you only need to force stop your AOL Mail app and then restart it to resolve the issue. Refer to these steps to restart your AOL Mail app on your iPhone:
● You need to double press the Home button of your iPhone device.
● Then swipe up on the image of the Mail app to close the app.
● After that, you need to re-launch the Mail app and check if the issue of not working is resolved.
Remember these steps will work only for iOS 9.3 and later versions. If you still cannot access your email, you can call AOL Customer Service Number and ask for an expert's help.