What is the performance of SMS being hacked?

Unable to send SMS, SMS sending status is unknown.

1. Unable to send SMS: When sending SMS to the blacked-out number, you will receive an error message, indicating that SMS cannot be sent to this number because the other party's mobile phone or service provider blocked SMS.

2. Unknown sending status of SMS: Send SMS to a blacked-out number, and you will find that the sending status of SMS is always sending or undelivered, because the other party's mobile phone or service provider blocked the SMS, or the other party's mobile phone has no signal or is turned off.