Copy Related Data from sheet one to another

[mikyas]

I have a special file called WEEKLYREPORT which has approximately 500 Item Codes with the current inventory on Column XX. I have SALESREPORT which has the same item codes (repeated item codes with with different sales invoices number). I need to have a vba code to copy all items from SALESREPORT and pasted in the WEEKLYREPPORT. I need the duplicate codes from SALESREPORT file to be copied to WEEKLYREPORT and reduce the inventory.

WEEKLYREPORT file is the master file. Any help would be highly appreciated.