The DJI app is not reliable for finding flight restriction zones, in the UK at least. The actual zones can be smaller and the positions is slightly different.
The DJI app is not giving pilots permission to fly as many people are led to believe, it only assumes that you have sought permission and the unlock code is you confirming that. In my experience, speaking with airport control towers is simple and pleasant. Each one is different, most of the time they want a form filled out and that's it.
There is only one app to go by that is built by air traffic control called Drone Assist and allows pilot to post information about their flight(s).
Take care!
Thanks for the explanation. I will be even more careful when flying in restricted areas.