In the same room, why would the data sent be lost? What could be causing this, and how can it be resolved?

[lvjinghua1125]

In the same room, why would the data sent be lost? What could be causing this, and how can it be resolved?
Could you please help me answer this question? thank you very much~

[lvjinghua1125]

The sent message will be lost.

[lvjinghua1125]

The message history in the room will disappear after a certain period of time.