I'm interesting specificall in the post off. After supplying a URL I attempted to capture (broadly) what you were sending back when call was complete. Your system was accessing our 'return' page, but it wasn't posting anything once call was completed. Do you have an example code for the ~\StatusChangePostURL(" . ALERTD_POST_STATUS_URL . " so we may capture that and update it in our database?
You can find more details about StatusChangePostURL and how it works here: StatusChangePostURL