To fix this issue, please try the following steps:

1. Download the latest version of the soundcore app from your app store. If you already have the app, we recommend uninstalling it and then downloading it again, as overwriting the installation is not recommended.

2. Pair your earbuds with your phone. Currently, the soundcore app does not support computers.

3. Open the app, tap the grid icon at the bottom left corner to enter My Devices, then tap "Add Device." The app will automatically connect to soundcore Liberty 4 Pro. 

Note: You must enable location permissions the first time you use the app.

4. If the connection fails, tap Set Up Manually > Liberty Series > soundcore Liberty 4 Pro to check if it can be added manually. If you can't find the model, please take a screenshot of the page and send it to us.

5. Go to your system settings, locate the language and region options, and switch the system language to English (United States).
 

6. Ensure the phone isn't connected to other Bluetooth devices. If so, disconnect them, then try connecting through the app again.

7. If the issue persists, uninstall and reinstall the app, then log in again.

8. The device system below iOS 13 (excluding iOS 13) does not support connection with soundcore Liberty 4 Pro.

If you still cannot connect after the above steps, please provide your mobile phone model, app version, and screenshots from step 4 to our customer service.

If the first connection was successful but subsequent connections fail:

1. Check if Dual Connections is enabled. If the app is connected to phone A, it won’t connect to phone B. Exit the app on phone A and try again.

2. Restart the device or try connecting with a different device.