ODataException: An undeclared property 'aaa_xxxxxid' which only has property annotations in the payload but no property value was found in the payload

If you get the error: then know this: case matters and the field name is the schema name of the field!

An error occurred while validating input parameters: Microsoft.OData.ODataException: An undeclared property 'aaa_xxxxxid' which only has property annotations in the payload but no property value was found in the payload. In OData, only declared navigation properties and declared named streams can be represented as properties without values.

Please note that the field names are case sensitive and go by the “schema name”. In my case, the schema name was ‘aaa_XxxxxId’. Once that was fixed the code began working!

var entity = {};
entity["customerid_account@odata.bind"] = "/accounts(21876381-dc67-e811-a954-000d3a378ca2)";
entity["aaa_XxxxxId@odata.bind"] = "/aaa_xxxxx(c9edf6c0-d670-e811-a958-000d3a3780dd)";
entity.caseorigincode = 1;
entity["msdyn_incidenttype@odata.bind"] = "/msdyn_incidenttypes(6760f919-77b0-e811-a95c-000d3a378f36)";