GPS is not enabled but isProviderEnabled() is returning true

I can check if GPS is on or not using isProviderEnabled(). If it is not on, I am launching intent so that user can enable GPS.
At the end I am again checking if GPS is enabled by user or not.
If user does not enable GPS and come out, still isProviderEnabled() is returning NULL.
What could be the issue ? Please guide me.

    String provider = LocationManager.GPS_PROVIDER;
     // Check if GPS is enabled
     boolean enabled = myLocationManager.isProviderEnabled(provider);
 
     if (!enabled) {
                     // GPS not enabled
         Log.d("", "Provider " + provider + " is not enabled");
         Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
         startActivity(intent);
                     // Consider the case when user does not enable GPS and come out. 
     } else {
         Log.d("", "Provider is enabled");
 
     }       
 
             // Re-check if user has enabled or not. (Note: case: user has not enabled GPS)
     enabled = myLocationManager.isProviderEnabled(provider);
     if(!enabled)
     {
 
         Log.d("","provider not enabled");
     }
             else
             {
                     // Control is coming here though user has not enabled GPS in settings
                     Log.d("","GPS is enabled");
             }
 

Thanks,
Biplab

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