I have a system in place that sends text message notifications out to users' cellular phones using their provider's SMS gateway email address. For example, if a form is filled out on a user's website the system will send an email to <phone number>@vtext.com (for Verizon subscribers) letting the user know that the form was filled out.
This system no longer appears to be working for Verizon users. The email logs report that the email has been accepted by vtext.com but the text message never comes to the recipient's phone. Nothing has been changed on my end and this system seems to still be working correctly with other cellular carriers.
I can still send messages to the Verizon SMS gateway addresses and have them come through as text messages when doing so manually through a regular email account and sometimes these automated messages still go through so it doesn't appear that the system is entirely broken or that our mail server is being blocked.
I was hoping that someone here could tell me if this is a temporary issue or if there's something I need to change about the way these messages are being sent or the content of these messages so that they will start going through again. Thanks.