GST Purchase and Sales Report


I have a client, who is using NAV 2013, AU Version, Base Built without any hot fixes. I would to assist my client to VAT Reporting.

I have noticed that both GST Purchase Report and GST Sales Report have duplicate/multiple entries. For Example: If I purchase two items one with VAT and one VAT FREE, the system records multiple VAT and VAT FREE entries. If I use the GST Purchase Report to view both VAT and VAT FREE values, they are over stated, due to multiple entries. If however only one VAT or VAT FREE item is purchase the system only records one VAT or VAT FREE entry respectively, which is correct. Only when there is a combination of both VAT and VAT FREE entries, I face this issue.

I have tested Cronus Demo Database, its working correctly. I have checked the Sales and Marketing and Purchases and Payables setup tables, contents from both table are identical. What can I be missing?

I originally implement the Client Navision using Cronus Demo Database, where I created and new company, took a backup of it and restored it at client site. the database was completely empty. Than all posting groups, Sales and Marketing and Purchases and Payables setup tables were setup, using Cronus Database as a template. After implementation was complete, realized a few weeks later that GST Purchase and Sales table have duplicate data, inserted automatically while posting.

Is there something which I have missed, which is causing this problem.