You need to disable the caching on the payment page & cookies to make all function works correctly.
How The Payment Workshttp://demo.goodlayers.com/traveltour/how-the-payment-works/
Setup The Payment Page
Go to “Tourmaster Plugin Option > General > Payment Page” to set up the payment template and sidebar.
Setup The Payment Gateway
At the “Payment > Payment Settings Tab”, select the payment method you want. You can learn more about how to obtain the payment API key in the next section.