Sales Contract : How to bring the Lines DFF field to BPM Approval flow?

Summary:

In Sales Contract under Lines Tab, we created an DFF field but the same DFF field is not coming in BPM Approval flow list for the condition.

Content (required):

In Sales Contract under Lines Tab, we created an DFF field but the same DFF field is not coming in BPM Approval flow list for the condition. How to bring the Contracts Lines DFF field in BPM Approval flow as a condition?

Version (include the version you are using, if applicable):

23C

Code Snippet (add any code snippets that support your topic, if applicable):

NA