Error updating a grid

[Tailgun]

I have a form with Component one True DBGrid 8 it is bound using ADODC control with this code and the grid is set to allow update.

Select *
FROM tblPayAppLineItems INNER JOIN tblProjectLineItems
ON tblPayAppLineItems.LineItemID = tblProjectLineItems.LineItemID

If I make a change to any cell I get this error when trying to update.


"Insufficient Key Column Information for Updating or refreshing".

run-time error 2147467259(80004005)

Any idea why I can't update ??

Thanks for any help in this matter.