Upgrade WePay API version in the following manner:

1. Login to WePay main account.
   
   WePay home page
   
   
   
2. Click on the site's account (for qa01 it is LXA2) to enter Accounts home page
   
   Account home page
   
   
   
3. Click on the account dashboard's configure tab.
   
   Account Dashboard
   
   
   
4. Click on the “Upgrade” button in the “API Version” section to upgrade the API Version of WePay.
   
   
   
   
5. For reference please refer “Full Upgrade” section in https://www.wepay.com/developer/tutorial/versioning