When you come across a situation where AOL mail not working on iPhone, then it could possibly be due to outdated app version or server related issue. But there could be other reasons responsible for the same. To fix it, you should immediately install the security updates from your AOL account or reboot your device to restore connectivity. If the issue persists, you should reinstall the AOL app on your device. Apart from this, you may also try to clear the cache as well as browser history to fix this problem.