Unicom mobile phone number SMS group sending is blocked by mobile. What is the reason?

1, it is very likely that someone reported it.

2. Mass transmission (each region is different, you can check the local mobile operator's restrictions on the quantity).

3, massive content, involving sensitive words.

4. There are bad short messages reported by Mobile, and mobile phone users can forward the received short messages that are considered as spam messages to the mobile special reporting platform with the code of 10086999.