Why can't yf link after installing Android 60 on Samsung mobile phone?

The following actions are recommended:

1. Check whether the mobile phone network connection is stable, and suggest replacing 3G, 4G network or wireless network.

2. Try to update the software version.

3. Click on the mobile phone application-Settings-Application Manager-All/Download-Click on the problematic software-Clear the data.

4. Back up data (contacts, text messages, pictures, etc.). ) and restore the factory settings (Settings-Reset-Restore Factory Settings).