eugenevdm on "[Plugin: Visual Form Builder] vfb_action_confirmation called twice when form is submitted"

I had a similar question because in my case it sent two SMSses connected to a BulkSMS gateway.

I found this link:
https://github.com/mattwithoos/WP-VFBP-2-SF/blob/master/wpvfbp2sf.php

Essentially install some session code setting and checking before sending.

if(!isset($_SESSION['RUNS'])) { // Prevents 'issue' caused by WP Visual Form Builder Pro where it runs script twice
$_SESSION['RUNS'] = 1;
}

if($_SESSION['RUNS'] == 1) {
// Do something

// your stuff here

// At the end
$_SESSION['RUNS']++;
} else {
unset($_SESSION['RUNS']);
}