Order data migration - Fulfillments 'Fulfilled' field not updating with past date

Hi Team,

I’m migration order data into Shopify using Admin REST API, I need to migrate orders, Fulfillment and Tracking information. I’m not able to updated the Fulfilled date with actual Fulfillment date present in the legacy system. Fulfilled date is showing as record created date.

Please advise how can the Fulfillment date from Legacy can be migrated into Fulfillment resource.

Thanks & Regards,

Anil