Restart the device and launch iTunes again
Some basic troubleshooting tips on whatever platforms:
Why does iTunes refuse to boot? And what should you do when iTunes won't start on Windows, or any other OS? Please keep reading on this post on iTunes won't open workarounds. Generally, the 'iTunes not opening' issue often occurs on Windows (10/7) PC, especially after new iTunes or Windows update.
There are a large amount of question results online about ' iTunes won't open' that clicking the iTunes icon but nothing happens. If iTunes won't open on your Windows PC, Mac all of a sudden or after update, here are a few ways to give it a kick start.