If you change the lock screen avatar and signature in the X9 mobile phone, you can try the following methods:

You can enter the I theme and set the lock screen style of the mobile phone to "light and simple" or "light and pleasant"; Then, in the screen lock interface, click the screen lock avatar to slide down (some models hold down the screen lock avatar for a long time), and click the "+"sign in the pop-up interface; After jumping to the setting interface, you can edit the nickname and personalized signature, select the color, and finally save.