1 - Log in to the vault at https://portal.secure-online-booking.com/
You will see something like below:
2 - Click the "Click here to enable SMS text messages" button.
3 - Enter your phone number in international format. (+3538571958585)
4 - Click Submit.
5 - You will receive a text message (to the number you entered) with a security code.
6 - Enter the security code number in to the field on the verify phone number page.
7 - Click Submit.
8 - Enter your username and password again.
9 - You may need to receive a pin again if you haven't checked the box to "remember this browser"
10 - That's it. Now when you log in you can have the security pin sent via text by changing the option in the drop down.