This worked for me!
Re: is it possible to get the push notification prompt back after you have pressed "don't allow"
I found a post on the web that told me to go to settings > notification center > go to the app that you need push notifications for, open it and make sure that all badge app icon, sounds and alerts are on for the app, then go back to settings and turn "airplane mode" off for 30 seconds then back on....I then had push notifications active again for that app. Happy Happy Happy!
Hope this helps! It worked for me! 🙂