Is there any restriction on sending text messages by mobile phone?

This has nothing to do with cell phones. It is a measure taken by mobile phone operators to prevent mass mobile phones according to the regulations of the Ministry of Public Security. When a mobile phone number sends too many short messages in a short time, the mobile grid system will limit your mass sending and avoid spam messages flying all over the sky. If enterprises really want to send non-spam messages in groups, they can apply to mobile companies for a platform for sending messages in groups. Use the platform to send mobile phone numbers.