Recently, I tried to setup the parking and had to inquire about this message. Their reply was:
Within your account approval email, there is a verification link that is provided with the details to enable your parking.
For the Parking Pages to work- Also ensure the following steps have already been done:
While logged into your DomainNameSales account, copy/paste the url below into your address bar and follow the instructions to Enable parking for your account enter your contact information
https://domainnamesales.com/sales/parking/verification
Update Parking Name Servers: (at the current registrar)
BUY.INTERNETTRAFFIC.COM (208.87.35.120)
SELL.INTERNETTRAFFIC.COM (176.74.176.170)