Finish a IOS/Google app for a New TTRPG

I hired a mobile app developer on here. They created an app that performs the functions i need. Although we were wanting to add more. However he was unable to get the app approved by google and so the app is useless. Google has warned if i submit the app and it continues to fail my account will be banned. I need someone who can refine the app and help me get it on the google store. The app did get onto the Apple Store but i need it on both apps. Further i need to complete the app for both platforms. The app is to manage a tabletop role playing game. A game like dungeons and dragons that we are developing. He drained our resources signigicantly but we need help to get this up and running. Apply tot his job