SMS verification is the default setting.
Click the "security settings" in the personal center, and change it in the 2-step verification method column according to the following steps.
How to use SMS verification:
1. Click "Mobile"
2. Click "Get Code" and enter the 6-digit code you receive.
3. Enter your Google authentication code.
4. Click “Confirm”.
How to use Google verification:
1. Click "Google"
2. Click "Get Code" and enter the 6-digit code you receive.
3. Enter your Google authentication code.
4. Click “Confirm”.