Text Message "Not sent. Tap to try Again"

I have five different phones on my account and ALL of them do the same thing.  From what I've read and tried so far there is no fix and we are switching phone companies again.  Sometimes it takes fifteen minutes plus before I receive the "couldn't send" notice.  Completely unacceptable and what's even worse is that I don't see any information that TMob is dealing with the issue. From what I'm seeing my last ditch effort would be to upgrade my plan and throw more money away.  We're going.