You must bind a mobile phone number.
You must bind a mobile phone number. To ensure the security of your cloud resources, you must bind your mobile phone number to your Alibaba Cloud account. This prevents your cloud resources from being disabled due to account theft. If your business requires a large number of cloud resources, we recommend that you also enable TOTP verification to protect your account. For more information, see TOTP verification.
After you bind a mobile phone number, you can change it to another mobile phone number in the Account Center console at any time. For more information, see Modify a mobile phone number.