SOAP API for updating the shipment line level DFF

Summary:

We need to update the Shipment line DFF through SOAP API. But we are unable to find and perform the same through Update Shipment API

Content (required):

We need to update the Shipment line DFF through Webservice SOAP API. But we are unable to find and perform the same through Update Shipment API.

Kindly suggest how it can be done?

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

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