Suggestion:
System has the provision to change /amend a Purchase Contract document even if it is already confirm.
User should use the Purchase Contract Amendment screen to make the changes in confirmed contract.
Amendment to the confirmed Purchase contract is done through this window. SCM-Purchase-Contract-Purchase Contract amendment
Purchase Contract Amendment comprises of 3 screens:
1) Purchase Contract Amendment header, to view and edit the header data such as valid from and to date etc.
2) Amendment Details, to view and edit the item details data.
3) Amendment terms, to view and edit the amendment terms data