What does the refund SMS limit mean?

For some reasons, such as operator's signal problem, short message content violation, etc. The short message sent by the user was returned, resulting in no deduction of the short message fee. The user's SMS fee will not be reduced because the SMS is returned, but will be deducted according to the original fee. There are many reasons why SMS is returned, including signal problems, illegal SMS content, wrong number input, etc. If the user finds that the short message has been returned, he can contact the customer service of the operator in time for processing.