How to change the mobile phone card of China without changing the number?

Please change your card at the communication office 100, 2 yuan/Zhang. 1. Customers who can receive the random code of SMS: You can directly change the card with a valid SIM card (or random code). 2. Customers who can't receive the random code: car owners who have completed the real-name registration system (verification) shall handle it with valid identity documents; Customers who have not completed the real-name registration system (verified) shall be handled with valid ID+service password+call record. In order to ensure the rights and interests of customers and property safety, it is necessary to take photos at present, and make up the card with "one person, one card" (both taking photos and taking photos).