PBA:Problem getting prices for mailbox options under Hosted Exchange

Hi

I am new to PBA and need help to get through the below mentioned requirement:

I have the subscription methods for the service Hosted Exchange under Web Hosting ie.
Exchange Basic 1+ user
Exchange Metered 1+ user
Exchange Unlimited 1+ user
Exchange Basic 5+ Users
Exchange Metered 5+ users
Exchange Unlimited 5+ Users
Exchange Basic 25+ User
Exchange Metered 25+ users
Exchange Unlimited 25+ Users

I need to get all the mailbox options along with their pricing that comes under each subscription method(basic, metered, unlimited) for Hosted Exchange service.

Please let me know which Parallel API method I should use to get these plans and their corresponding prices.
Have tried using methods "PlanCategoryDetailsGet_API" "PlanPeriodListGet_API" from PBA but getting error "Server returned a fault exception [-1].

Thanks
Nidhi Jain