I downloaded YY Backup on my phone, and then backed up my contacts, calendar and text messages. I used QQ to log in, and then I restored the phone to its factory settings.

Because you have set up the mobile phone and the backup data is

on the mobile phone, it will not work.

Otherwise, the only way is to restore the data on App Store.

This is the data restoration function above.

Connect your phone to your computer and use this function to

use your phone stably.

It can not only ensure the stability of mobile phone data, but also be easy to operate.