Mandatory DFF Validation Error on AR Invoice When Field Is Hidden for Specific BU

We have created a Descriptive Flexfield (DFF) Job No. on the AR Invoice page and marked the segment as Required.

Requirement:

The DFF (Job No) should be mandatory only for specific Business Units. For one BU, we have hidden the DFF using page personalization on the AR Invoice creation page.

Issue:

For the BU where the DFF is hidden, users are still receiving a validation error during invoice creation:

“Please select Job No”

Even though the DFF is not visible on the UI for that BU, the system continues to enforce the mandatory validation.

Observations:

The DFF segment is marked as Required at the setup level.