What card of mobile phone can't send text messages? Recently, China Unicom and China Mobile can't send it, and banks and Alipay can't use it. Customer service said it couldn't be solved.

Hello, if you send a lot of short messages, the mobile phone can't send short messages for a short time, but it will resume later. If you really need to send a lot of messages, Unicom now has a short message assistant service, and you can handle this service. Enter the mobile phone number of the SMS receiver (similar to the function of mass SMS, you can click "Import Directory" to select more numbers from the drop-down list and send them to 1000 friends at most) and the SMS you want to send, and click Send.