Do you know the cause about the failure of Import Project?

Summary:

Do you know the cause about the failure of Import Project?

I would like to import Project with FBDI .(https://docs.oracle.com/en/cloud/saas/project-management/23b/oefpp/importprojects-3216.html#u30240692)

But it is failed and appeared error massage " The value of the attribute TASK_NUMBER OR PRED_TASK_NUMBER isn't valid."

I entered valid tasks that is entered in Tasks sheet in Task Number and Predecessor Task Number in this sheet.

Do you know the cause?

Please let me know.

Thanks,

Mayuko