Cause analysis:

1. A red exclamation mark appears in the chat message, indicating that the message transmission failed due to network reasons. Please resend it later. If this problem occurs for a long time, change the access point of the mobile phone network, such as Wifi. Just log on to wechat again.

2. Party B blacklists itself. If the sender does not receive it, a red exclamation mark will appear. And if you resend it, it's still an exclamation point, and you need to add friends to re-verify it.

Extended data:

The function of Mo Mo:

Social mode: locate strangers and groups around you according to GPS search, establish contact efficiently and quickly, and save the distance cost of communication.

Free sending: Send SMS, voice, photos and accurate geographical location through Momo for free, and interact with TA conveniently and quickly.

Thoughtful sending: know the sending status of information immediately, and prompts such as "sent, read" can let you know whether the information is seen by the other party in time.

Personal data: eight photos can be stored, as well as signature, occupation, hobbies and so on. Enhance others' understanding of themselves on the information page.

Scene facial expressions: The emoticon store provides rich facial expressions, which makes the chat more lively and conforms to the chat habit of mobile social interaction.