New Drivers do not receive SMS

Dear Support Team,

I have been using the plugin for almost a year, and definitely loving it, tbh, what a great plugin. Recently i received an issue, when i register a NEW drivers and then assigned them for the orders they do not receive the SMS, however, all old drivers are receiving the SMS accordingly.

Looking for any help.

thank you.

The page I need help with: [log in to see the link]