109. Is it possible for the messages sent using a short code to be blocked?

Yes. a few carriers like Simple Mobile & T Mobile do block messages from short code if requested by the end user.

Important Announcement!

URGENT! Please register the 10-digit business phone number (e.g. 555-555-5555) that your organization uses to send texts to consumers in the U.S. Failure to register may cause heavy penalties and disruption to all your text messaging communications.