Rest API - Get Order Not working on Sandbox

[salsha7566]

https://api.sandbox.ebay.com/sell/fulfillment/v1/order/110553947168-29059256xxx
The above REST API not working in a sandbox. I am passing Authorization and Content-Type in a header.

After being given a call, eBay returned an unclear error message.

{

    "errors": [

        {

            "errorId": 30500,

            "domain": "API_FULFILLMENT",

            "category": "APPLICATION",

            "message": "System error."

        }

    ]

}

[five_notch_trading_post]

if you add an Accept header, does the message change?

"Accept": "application/json"

[salsha7566]

Thanks for the reply but still has the same error.