Fetion sends text messages in groups, adds a contact, and the screen becomes black. What happened?

There are two possibilities. The first is the customer service terminal of Fetion itself. Because the users who use Fetion now are basically negligible, there may be no artificial background maintenance related to Fetion management, which has caused this situation. However, no one will know. Secondly, if your mobile phone is a customer service terminal, it may be a black screen due to memory problems at runtime, or it may conflict with the security software that comes with your mobile phone. Thirdly, if you need to send a lot of short messages, I suggest you use the onesmser short message platform.