PO line status is blank for the POs in 'Pending Approval' status

Hello,

I have created a PO with 2 lines. As per the approval setup, these 2 lines should be approved by 2 different approvers.(Cost center manager approval)

Once I submit the PO, the PO header status becomes pending approval which is expected. But at line level the status is blank for these 2 lines. The expectation is, the line status also should be 'Pending Approval' until it becomes approved.

Below are the scenarios I observed,

1. Both line approvers are not yet approved and the line status is blank instead of 'Pending Approval'
2. If one of the line is approved, the corresponding line status should be 'Open'. But even after approving one of the line, the status is blank instead of Open.