Commerce booking

Afetr installing commerce booking and configuring it by adding commerce booking field to a content type.
I created an event type product which displays the way I wanted, but the issue comes in when I click the book button. it display the following error::::::::::
EntityMetadataWrapperException: Unknown data property commerce_customer_billing. in EntityStructureWrapper->getPropertyInfo() (line 339 of /Applications/MAMP/htdocs/drupalkickstart/profiles/commerce_kickstart/modules/contrib/entity/includes/entity.wrapper.inc).

I think I am missing something . . . .

Posted: Aug 16, 2013