What is the reason why Xiaomi 8' s mobile phone broadcast SMS card died?

Since April, there have been five Xiaomi mobile phones at home, all of which have this problem. Some models of the system have not been updated, but the update in Xiao Ai is automatic. At present, the version of Xiao Ai is April 10, so it is initially suspected that the update of Xiao Ai is a Bug. I can only say that I will wait for the update. If I'm not used to it, I can turn off the sound like me (Settings → Xiao Ai).

In addition, there is an untried solution. At present, my mobile phone has 7K+ SMS. I wonder if it will alleviate the problem by restoring the factory settings and replacing it with asynchronous data of a new mobile phone.