Project Purchase Invoice error "The state of the source document or source document line could not be updated."

Hi All,

I have created Purchase Order for Project from Project Management and Accounting Details. But i am going to post Invoice it is giving me below error :

I have searched over internet about this error, but not successful yet. I would like to show you Distribution for my PO line (PO Line >Financial > Distribute amount ) which is showing red mark see below:

Please help me on this.