Method 1
You need to delete cache and data from Google play store. Follow the steps to do that.
> First go to Settings.
> Tap Application and then All.
> Search for the Google play store and click on that.
> You can notice two buttons there, Clear cache and clear data. Press the buttons one by one to clear the c cheand data from Google play store.
> Return to the application again and press Download manager to clear the data from there as well.
> Go back to home screen and open Google play store once again to download the app.
Maximum chances are there that the problem will be fixed now. You can also try the second method.
Sometimes slow Internet connection has been proved to be the reason of this 919 error. So, changing thenetwork connection can help to fix Google play store error 919.
If you were using mobile data connection for downloading, then try to use Wi-fi or else use mobile data connectionif you were unable to download using the Wi-fi connection. But if the size of the app is more than 50MB then this isnot possible and you need to follow the first method.