Debug a short API script.

I have a PHP file that needs to be debugged. This PHP file integrates with Txtnation API to send premium text messages. What we want to achieve is to be able to send out the 2nd and 3rd text messages after user unsubscribes... for example: $secondstopmsg = 'You have opted out of XXXXX. You will not receive further charges. Call us at XXXXX. Thanks'; $thirdstopmsg = 'Thank you for using our service. If you would like support please write to XXXXXX'; Currently the 2 messages above are not able to be sent out after user unsubscribes. Will provide further details once project is accepted. Please see attached documentation.