Push notifications for Yahoo mail

For the past week, my Yahoo mail "push" notifications have not been working. I have gone into settings and see that all of them are set to "fetch" and when I go to change it, the "push" notifications availability is no longer an option for Yahoo. I knew that Gmail did not use "push" but Yahoo has always had that option.

I have reset my phone several times but still the notifications are not working.

I have the iPhone 6 Plus and am using the latest Apple software. I updated it several months ago.

Does anyone know what I can do? Or has Yahoo changed how they send notifications?