SMS problem where do things go?

I have a little app that sends an email in such a way that it will actually send an sms (thru a third party). The third party gives me an smtp server and port, and an account to send to in order to make this happen. When I deploy to Volt, no go.
I put this header in extraheaders;

<script src=""></script>

The little app is attached. They don’t see anything wrong with the code - I think I likely have to put something somewhere in appStudio. Thoughts?
(this is just a demo acct)