For security, and to prevent fraud, you must verify your phone number to make a purchase on the site.
Follow these instructions to do this
- On the checkout page, enter your 10 digit mobile number, then click on VERIFY YOUR PHONE 

 - You should then receive a code to your phone
 - Enter this code into the box which appears on the checkout page
 - Click VERIFY
 
You can then continue to create your account / checkout