Step 1:
Position your mouse cursor over “User” avatar on the upper right corner of the page then click “My Wallet”.
Step 2:
Navigate to "Settings" -- "Account Management".
Step 3:
Click the Link button in the Phone section and Input your phone number，or click Unlink to unbind your phone number by yourself.
Step 4:
To link your phone, On this next page, please select the country, input the phone number you wish to bind with and click Send.
To unlink your phone,then you just have to input the SMS codesas required.
Step 5:
Input the SMS code which was sent to your phone to complete the process.
If you have not bound the Google Authenticator yet, then you do not have to input the Google Authenticator code.