Upgrades and error fixing in my existing Android app

PLEASE ONLY BID IF YOU CAN WORK FULL TIME (6-7 hours per day) PLEASE ONLY BID IF YOU CAN WORK WITH TEAM VIEWER. My app is an android app written in java. The applicant should have knowledge of java and server side coding too. I want FULLTIME FREELANCER only working at least 7 hours a day for me. Want all the upgrades finished in an error free way AS SOON AS POSSIBLE.. MAJOR UPGRADES 1. Only 1 account per device No multiple email accounts 2. Fixing app crashes 3. Adding two adpartners 4. I want a automatic/manual switch for rewards from remote configuration. Where I can select automatic/manual rewards at will. 5. Firebase push notification is not working. I want one where a user gets notification as soon as they open the app before the user starts to use the app. 6. When I publish an update, user should get a notification when they open the app with update link in the notification. And the user should not be able to use the app unless they update. There are 9 minor upgrades too. Minor upgrades are small design and text changes in the app which will take less than 10 mins per upgrade.