Iphone backup failed

Hi Ilyaaaaa,

Thanks for the update. Are you backing up the iPhone using iCloud? If so, let's check your iCloud storage to see if this could be causing the issue. This article will show you how:

Manage your iCloud storage

If storage isn't the issue, make sure you're connected to a reliable Wi-Fi network. Next, connect your iPhone to the power cord and lock the screen in order to see if it will try to create a backup again.

If the issue persists, contact Apple Support: Contact Apple for support and service - Apple Support

Take care.

Hello Ilyaaaaa,

Welcome to Apple Support Communities! We understand you're having trouble clearing the notification off of your screen. We're happy to assist you with this.

You took the right step by restarting your iPhone. Now let's try to close the Settings app and reopen it to see if the notification still appears. You may want to restart again after closing the app:

Close an app on your iPhone or iPod touch - Apple Support

Restart your iPhone, iPad, or iPod touch - Apple Support

Best Regards.