Delta api does not return "@microsoft.graph.sharedChanged": true for SharePoint drives

Hi,

I want to scan drive to check for permission changes on files and folders, in delta api documentation it is mentioned that "@microsoft.graph.sharedChanged": true will be returned for items having permission changes. Request url and headers are as per below
Request : https://graph.microsoft.com/v1.0/sites/<site_id>/drives/<drive_id>/root/delta?token=<delta_token>
Header : prefer: hierarchicalsharing,deltashowsharingchanges,deltashowremovedasdeleted,deltatraversepermissiongaps
But that does not seem to return sharedChanged header for most of the cases. I am using delegated permissions here. Other CRUD cases on items seem to work okay with delta APIs.

Thanks.