Manufacture Part Number and Manufacture Attributes in PO or PR

Summary:

Hello, 

I have an issue and I appreciate your assistance.

I want to use the attribute of Manufacture Part Number and Manufacture in PR and PO.

Created a sample item - Test Manufacture

I created 2 manufacturers:

TESTMANUF1000

TESTMANUF2000

I created a Manufacture Part Number and linked the manufacturers accordingly.

XXXTESTMANUF1000

XXXTESTMANUF2000

And finally, I linked to the Test Manufacture item

But when I created a PO

Manufacturer Part Number and Manufacture

1. Not reflected in the order

2. I expect the Buyer to be able to select the appropriate manufacturer, but this field is off

Could you please provide guidance on how to address this matter, maybe missing Role, Privilege, or Data access?