Q: Can't update solfware and Can't down any app

Howdy Bao Duong,

It sounds like you are trying to download anything from the iTunes Store but nothing is coming down whether it's updates or apps, or songs. I would first quit the Settings, iTunes and App Stores:

Force an app to close in iOS

1. Press the Home button two times quickly. You'll see small previews of your recently used apps.
2. Swipe left to find the app you want to close.
3. Swipe up on the app's preview to close it.

 
When you have done that restart the device and test the issue again:

iOS: Turning off and on (restarting) and resetting
 
If the issue persists, I would suggest you use this article to help troubleshoot issues accessing the iTunes Store:

If you can’t connect to the iTunes Store

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