“Verification failed your phone is no longer connected To Internet “

If your iPhone, iPad, or iPod touch won't update - Apple Support

hello,

i am having the same error and i have tried multiple network connects as well as connecting to itunes on a windows computer and on a mac.

What part can't you understand? In your case, the article tells you to either try using another wireless network or to connect your iPhone to a computer to perform the update.