1.Network error
Please check your internet connection, turn off and on your Wi-Fi or mobile data, and try sending the message again.
2.The sender is blocked by the receiver
You may try to contact them via other methods, like email.
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3.A Potential security risk
The messages have been classified as spam. Alibaba.com employs an anti-spam system that scrutinizes all messages sent through communication tools.
If identical messages are sent repeatedly or if spam advertisements are included, the messages will be flagged as spam, and your account may face consequences.
Kindly utilize Alibaba.com communication tools for regular business negotiations and refrain from using them for disseminating marketing information.