Shopify POST Error to Custom App

Hi,

I am sending a POST request to custom App to Fulfill the orders in Shopify.
But I am getting the below error on POST : SyntaxError: Unexpected end of JSON input.

JSON is valid and same logic is working in Sandbox but not in Production.
When I am sending POST from POSTMAN, I am getting a login page link in response.

GET is working fine as I am getting the Order Data first and then sending a POST for fulfillment which means there should not be any authentication issue.

Please help!

Hi Manmeet,

Did you check your scopes on the production shop?

Often times a GET will work if you have a valid session with shopify, e.g. a tab open where you are logged into the shop.

Always try to work in an incognito window and not be logged into the shop at the same time… Often that has caused issues for me in the past.

Cheers,

Gary