You need to configure permissions for the Purchase order quantity flow.

To configure permissions for the Purchase order quantity flow, you should assign the run-only user permission to the finance clerk. This will allow them to run the flow without being able to edit or share it1. The other permissions are not suitable for this scenario because:

Co-owner permission would give the finance clerk full access to edit, share, and delete the flow, which is not necessary or desirable1.

Owner permission would transfer the ownership of the flow to the finance clerk, which would remove your access and control over it1.

User permission would not allow the finance clerk to run the flow at all, only to view it1.