The fact that the nickname on Douyin has been certified means that the name has been officially certified by others. This is the orange V and blue V numbers that we can see when browsing videos. These are all officially certified. Certified, you can no longer use this nickname.
How to register Douyin nickname:
Android10 oppok5 of colorOS7.1 system, software version Douyin 13.9.0
1. Open Douyin on your mobile phone and click Me, click Edit Profile next to your avatar.
2. Click on the name.
3. Enter the modified name.
4. Enter the name you want to change and click Save in the upper right corner.
5. If you see that your nickname has been authenticated, please register again.