Can I leave a message on the phone bill SMS?

This kind of short message is usually not allowed to leave a message.

Telephone short messages are generally sent and received through the operator's short message interface, but the number of characters in this short message is limited, generally only a few dozen characters, so it is impossible to send a long short message. In addition, the function of SMS is mainly used to pay the phone bill or check the balance of the phone bill, rather than sending and receiving personal messages.