sales order REST API update carrier ID

using REST API, want to update carrier ID

JSON
{
"ActionCode": "ORA_FOM_UPDATE_LINE",
"OrderRevisionReasonCode": "ORA_CUST_REQUEST",
"OrderRevisionComments": "Shipping Carrier",
"ShippingCarrierId": 300000047303475,
"requests": [
{
"FulfillLineId": 300000319764338
}
]
}

but it's always stuck with this error message "The request couldn't be completed because either it doesn't include a value for the BillToContactId attribute, or the value of 300000047394649 that it does provide isn't valid."