When a queue is closed or unattended, you can allow or prevent SMS messages from entering these closed or unattended queues. You can also send an auto-reply message to the client sending the SMS regarding the closed and/or unattended queue and their message. For further information, see Related Articles listed below. 

Related Articles:

• SMS to Chat - Allow SMS Messages into a Closed or Unattended Queue
• SMS to Chat - Prohibit SMS Messages from Entering Closed or Unattended Queues
• SMS to Chat - Prohibit SMS Messages from Entering Closed or Unattended Queues without Sending an Auto Reply Message