I have been trying to upload a mobile game I made on the Google Player store however its saying a mismatch. Note this is a brand new mobile app. I exported it aab package. I created the key from Android Studio.  The key was uploaded and approved however still having issues. I have done the below steps.

I follow these steps. I also uploaded a new key reset.

Step 1: Generate or Locate your Keystore File

If you already have your .jks or .keystore file, skip to Step 2. If you need to generate the file that matches your fingerprints:

1. In Android Studio, click Build > Generate Signed Bundle / APK...

2. Select Android App Bundle and click Next.

3. Under Key store path, click Create new...

4. Choose a path on your computer, set your passwords, fill out the certificate details, and click OK.

Step 2: Configure the Signing Settings via UI

Instead of editing the code manually, you can let Android Studio handle the build.gradle updates for you:

1. Open your project in Android Studio.

2. Go to File > Project Structure... (or press Ctrl + Alt + Shift + S on Windows / Cmd + ; on Mac).

3. On the left sidebar, click on Modules.

4. Select the Signing Configs tab at the top.

5. Click the + (plus sign) to add a new configuration. Name it release.

6. Fill in the details using your exact key information:

   • Store File: Click the ... folder icon and select your .jks or .keystore file.

   • Store Password: Enter your keystore password.

   • Key Alias: Enter the alias name you gave the key.

   • Key Password: Enter your key password.

7. Click Apply.

Step 3: Link the Signing Config to your Release Build

Still inside the Project Structure window:

1. Click over to the Build Types tab (right next to Signing Configs).

2. Select release from the list of build types.

3. Look for the Signing Config dropdown menu on the right.

4. Change it from $default$ to release (the configuration you just created in Step 2).

5. Click OK to save everything. Android Studio will automatically update your Gradle files in the background safely.

Step 4: Build your Release Bundle (.aab)

Now that your tool is configured with your upload key, you can build the final file for Google Play:

1. Go to Build > Generate Signed Bundle / APK...

2. Select Android App Bundle and click Next.

3. Because of your setup, the key path and passwords should automatically be filled out. Click Next.

4. Select release as the Build Type.

5. Click Finish.

Android Studio will compile your app and generate an .aab file in your app/release/ folder. This file is now signed with your upload key and is ready to be uploaded straight to the Google Play Console!