How to change application id in Android Studio
Every Android app has a unique application ID to identify your app in the Google Play Store. Which shows in the URL area on Google Play Store & Play console.
If you would like to update your app, the appliance ID (and the certificate you sign it with) must be an equivalent because the original APK—if you change the appliance ID, Google Play Store treats the APK as a totally different app. So once you publish your app, you can’t change the appliance ID.