AT&T LG K20 M255 Issues, LG Bridge Cannot check the software version.
The AT&T LG K20 M255 is not supported by LG Bridge. The device supports software update through OTA (Over-the-Air) only.
When you try to use LG Bridge to upgrade your AT&T LG K20 M255 smartphone, LG bridge will pop up an error message saying that ‘Cannot check the software version. Try again‘.
According to the LG official Support website, Software Update for AT&T LG K20 M255 only available Over-The-Air.
If you have not been notified of an available software update, you can manually check if one is available.
From the Home Screen, tap Apps > Settings > About phone > System Updates
Tap Update Now to manually check for a new update.