Some Sprint customers have stated that they have been having troubles receiving text messages from our short code to their mobile devices. We have found a solution to these problems.
You can text “Allow 71441” (that is “Allow” <space> “71441”) and text that to 9999. Once you do that, this will add the 71441 short code to the allow list and will move it off of the block list.
Once you submit that text, you should get a reply back from SprintFreeMsg stating “Text messages to and from “71441” are now allowed.
(Note- 71441 is US shortcode)