There is always a message sign flashing on the mobile phone interface, but there is no message in the inbox. What is the reason?

The message sign doesn't blink because you have unread messages. There are two reasons, 1, and the SMS inbox is full, which means it is stored in the mobile phone or SIM card, and the latter is more likely. 2. You received the multimedia message, but you haven't downloaded it yet, which means the content of the multimedia message is displayed. Cell phone reports count. So you'd better tidy up your SMS inbox,