What should I do if I don't change my number when I switch networks?

Legal analysis: go directly to the offline business hall of the operator who wants to transfer the network and ask the salesperson.

Legal basis: Regulations on the Administration of Communication Short Message Service

Article 2 These Provisions shall apply to the provision and use of short message services in People's Republic of China (PRC).

Article 3 The Ministry of Industry and Information Technology shall be responsible for the supervision and administration of short message service throughout the country. The communication administrations of provinces, autonomous regions and municipalities directly under the Central Government shall be responsible for the supervision and management of short message services within their respective administrative areas. The Ministry of Industry and Information Technology and the communications administrations of provinces, autonomous regions and municipalities directly under the Central Government are collectively referred to as telecommunications regulatory agencies.

Article 4 Those who provide and use short message services shall abide by laws, administrative regulations and relevant provisions of telecommunications regulatory agencies, and shall not engage in illegal activities by using short message services.

Article 5 Relevant trade associations are encouraged to formulate a self-discipline management system for SMS services according to law, and guide members to strengthen self-discipline management.