Integrated Import Declaration 069 - What does the error "GAC: LPCO missing or invalid document type for the program + commodity total value or currency + unit price or currency is missing or invalid" mean?

Please ensure that the following steps are taken:

Navigate to the Invoice section
Go to Invoice Details and select the Items tab
Under Item Details, check the LPCO tab for the Reference Number (e.g. GIP100 for HS Code 1101002000)
Ensure that the Canadian Document Type is set to 2004
Under the PGA tab, ensure that GAC is selected under Program for all items.

Houston, we have a problem!