Cannot update project data using DPR_DX_PROJECT

Dear Experts,

I import excel file using standard function for Portfolio Item creation (RPM_DX_ITEM), and also pass parameter to create Project on saving.

But when I need to change Project Management Project (e.g. add phases, tasks and checklists) using program DPR_DX_PROJECT, there is no option to update. I tried to put the Project Number into the file and upload, system shows the error message that object is already exists.

Could you please kindly help to advise the program for mass project update?

Thanks and Best Regards,

Anukoon P.