I have already an android app for a closed parking system. My app works fine except that my parking slots are not saved in a database which makes it visible. The app is linked to a firebase database,...

I have already an android app for a closed parking system. My app works fine except that my parking slots are not saved in a database which makes it visible. The app is linked to a firebase database, which is part of googletechnology. I have already created a firebase account and I am happy to share it with you if are willing to do the work. I managed to create an authentication connection with the application. However, when the user sign up on the app or enter their details for example to book a parking slot for car park number 15. The details are not saved on the firebase database, I need the app to pre-populate the database with parking data so the user can know the parking slot booked is for them and it cannot be booked by another user. The link below is for the current application. Please review it and if you can do the work I will provide you with the firebase login later. Thanks

https://ufile.io/nasja