Follow the following process to Build the project for production release
Step 1: Before starting the build process, please configure your app.json file which is located at the project root directory.
1.1) Put App name under “name” property.
1.2) Put version number under “version” property.
1.3) Put your app’s slug under “slug” property (lowercase without space).
1.4) The iOS “bundleIdentifier” and Android “package” fields use reverse DNS notation but don’t have to be related to a domain. Replace “com.yourcompany.yourappname” with whatever makes sense for your app.
1.5) VersionCode will increase by one every time the app gets a new version release. (I.e., For app version 1.0.1 versionCode will be 1, for app version 1.0.2 versionCode will be 2 and so on…)