Unable to Update App on Play Store After Migrating from Kotlin to Flutter

Question

I have an Android app that was originally developed in Kotlin and published on the Google Play Store two years ago. Recently, I rewrote the app in Flutter while keeping the same package name and uploaded it as an update to the Play Store.

However, when I try to update the app from the Play Store on a device that has the old Kotlin version installed, I get the following error message in the Play Console: "Try again, and if it still doesn't work, see common ways to fix the problem."

Steps to Reproduce:

• Install the old Kotlin-based app from the Play Store.
• Upload the Flutter version of the app to the Play Store with the same package name.
• Try to update the app via the Play Store.
• The update fails, showing the mentioned error message.

Things I Have Tried:

• Ensured that the package name is the same.
• Checked that the version code is incremented correctly.
• Signed the new app with the same keystore as the old app.
• Verified that the new app has the same applicationId in build.gradle.
• Reviewed logs but couldn't find any specific reason for the failure.

Why is the update failing when migrating from Kotlin to Flutter using the same package name, and how can I fix this issue?

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