Post fulfillments not working in our Development environment

We are doing the following call using POSTMAN on one of our development sites:

POST https://xxx/admin/api/2023-04/fulfillments.json

JSON Body:

{

“fulfillment”: {

“tracking_info”: {

“number”: “398760110772”,

“url”: “”,

“company”: “”

},

“line_items_by_fulfillment_order”: [{

“fulfillment_order_id”: “6366829674751”

} ]

}

}

We’re getting back a status of 200 (OK) but the order is not fulfilled and here is the response body:

<a

href=https://accounts.shopify.com/oauth/authorize?client_id=7ee65a63608843c577db8b23c4d7316ea0a01bd2f7594f8a9c06ea668c1b775c&destination_uuid=b15be861-8ebb-4bfc-a898-a6f872693ca2&nonce=19681ca4336e9ff8ca606ffc6aed670d&prompt=merge&redirect_uri=https%3A%2F%2Frsm-development-4.myshopify.com%2Fadmin%2Fauth%2Fidentity%2Fcallback&response_type=code&scope=email%20https%3A%2F%2Fapi.shopify.com%2Fauth%2Fdestinations.readonly%20openid%20profile%20https%3A%2F%2Fapi.shopify.com%2Fauth%2Fpartners.collaborator-relationships.readonly%20https%3A%2F%2Fapi.shopify.com%2Fauth%2Fbanking.manage%20https%3A%2F%2Fapi.shopify.com%2Fauth%2Fmerchant-setup-dashboard.graphql%20https%3A%2F%2Fapi.shopify.com%2Fauth%2Fshopify-chat.admin.graphql%20https%3A%2F%2Fapi.shopify.com%2Fauth%2Fflow.workflows.manage%20https%3A%2F%2Fapi.shopify.com%2Fauth%2Forganization-identity.manage%20https%3A%2F%2Fapi.shopify.com%2Fauth%2Fmerchant-bank-account.manage&state=ab378cc6a004f5597b8a2328eb362113&ui_locales=en&ux=shop>Continue

I cannot determine what is different on the development site vs production because I can do the same call on a production site and the order is fulfilled correctly.

Any help would be appreciated.

Issue resolved by clearing cookies in Postman.