What happened for the loop? did nothing display or did the message appear only once?
If it appeared only once, you need to put a function in that does nothing, to "reset it" or else (in my experience, anyway) you only get the last string sent of a loop.
If it didn't appear at all, are you sure you put the bit that actually sends it in the loop, or else it will only set the variable to your message, and then keep setting the var to the same value, and never actually get to the send command outside the loop. (if the loop is set only to happen, say 50 times, only the last one would send, so that could also be a reason it appears once)
Hope that helps.