Iphone4s Unicom mobile card imessage has been waiting to receive the activation message, but it can't be sent out for expert advice?

If your iPhone is a regular product in China and there is no jailbreak, you can try a different network, or it may be related to the iMessage server. You can wait a while before trying to activate it. If your iPhone has unofficial operations such as jailbreaking, please use iTunes software to back up data, and then try to activate iMessage after the system is running again. If this iPhone is not licensed, please contact your dealer to solve it.