You have created the Project Purchase Request and the request is created with account assignment to project header but not with specific project task assignment.
You have to manually update the Project Task in each line item in the purchase document.
SAP Business ByDesign
Reproducing the Issue
Go to Project Management work center
Navigate to Products tab
Select the product and create project purchase request
The account assignment in the purchase request and the follow-up purchase order shows the header project ID and not the project task ID
You are creating project purchase request for whole project, so available products will be picked for project purchase request creation and project header will be assigned in account assignment field.
Please create project purchase request with respect to the particular project task.
You can do so in Project screen->products-> select product-> create purchase request with respect to released project task.
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