To address your issue with the Offline Music Player - Weezer, follow these comprehensive steps to troubleshoot and resolve the problems with listening to and downloading songs:

1. Check App Permissions:
Ensure the application has the necessary permissions to access storage. Go to Settings > Apps > Weezer > Permissions, and enable storage permissions if they are disabled.

2. Update the App:
Applications can have bugs in older versions. Check if there's an update available for the Weezer app. Go to the Google Play Store, search for "Offline Music Player- Weezer," and tap Update if available.

3. Clear Cache and Data:
Clearing the app's cache and data can fix certain issues. Navigate to Settings > Apps > Weezer > Storage > tap Clear Cache and then Clear Data. Note that clearing data may result in loss of downloaded songs and settings.

4. Reinstall the App:
If the problem persists, uninstall the app and reinstall it. This can resolve issues stemming from corrupted files or incomplete installations. Go to Settings > Apps > Weezer > tap Uninstall, then reinstall it from the Google Play Store.

5. Ensure Internet Connection:
If you are trying to download songs, ensure that you have a stable internet connection. Switch between Wi-Fi and mobile data to see if there’s a change in downloading capabilities.

6. Check Account Status:
If your app has any subscription or account-login features, ensure your account is in good standing and that you're logged in properly. Sometimes access can be restricted if there are payment issues.

7. Consult Support Forums:
Visit online support forums or platforms such as Reddit where users share similar experiences. For example, users have reported issues on Reddit regarding the inability to listen offline or download songs in the Weezer app - learn more - learn more.

8. Contact Customer Support:
If none of these steps work, consider reaching out to the app’s customer support for further assistance. You can usually find contact details in the app or on its official page on the Google Play Store.

9. Alternative Solutions:
If the current version of the app continues to malfunction, consider exploring other music player apps that allow offline downloads, such as alternative applications recommended in various forums - learn more.

By following these steps, you should be able to resolve the problems you’re experiencing with the Offline Music Player - Weezer.