VBA not updating Pivot Table

Hi All,

With reference to the attached:
- This is part of a stock control spreadsheet but all other tabs have been deleted for commercial sensitivity reasons
- The tab 'Withdrawal Detail' exists so that a member of the stock control team can input the data noted on a 'Stock Requisition Form'
- Tab 'Withdrawal Summary' hosts several pivot tables (one per month) with summarises the stock withdrawal activity contained on the 'Withdrawal Detail' tab
- The VBA/Macro button on the 'Withdrawal Summary' tab updates these totals every time it is pressed (and it is pressed every time the 'Withdrawal Detail' tab is updated)
- The macro is updating the totals correctly for the pivot tables for Jan-16 - Jun-16 but the pivot table for Jul-16 is also reflecting the values of the month of Jun-16 contained on the 'Withdrawal Detail' tab.

Can somebody advise why this is happening and list a step by step walkthrough for correcting this?