Why is the tracking number not updating the second time on Shopify?

Hello Team,

We have done integration in between salesforce to shopify and we are facing issue with tracking number on shopify, tracking number is updated on Shopify at the first time however, when we try to update the tracking number from salesforce to shopify the 2nd time it gives the below error and the number is not updated.

Error: System.HttpResponse[Status=Unprocessable Entity, StatusCode=422]

JSON Body:

“fulfillment” : {
“tracking_number” : “3123456789”,
“tracking_company” : “fedex”,
“location_id” : “21769475”,
“tracking_url” : “https://www.fedex.com/fedextrack/?trknbr=1234567890
}

Please advise.

Regards,
Siyona Shah

Please add error screenshot.