How to authenticate a person's mobile phone number twice abroad?

It is impossible to authenticate the mobile phone number twice abroad, because the second authentication requires Chinese mainland's ID card.

If secondary authentication is not possible abroad, it is recommended to try the following methods:

1. Contact the customer service of China Mobile and ask if there are other ways to carry out secondary identity authentication and get detailed operation steps.

2. Try to use other trusted communication applications for identity authentication, such as WeChat.

Please note that communication security must be maintained during any online authentication to avoid revealing personal information or being cheated.