REST METADATA Describe not working

Hi,

We are trying to use the REST Metadata Describe calls with no success.  Our other calls are working OK - but not the DESCRIBE calls.

https://secure-slsomxuda.crmondemand.com/OnDemand/user/Rest/Latest/describe

ERROR is

{ "Error": [ { "problemType": "https://support.oracle.com/epmos/faces/DocumentDisplay?id=1663390.1", "title": "The server encountered an unexpected condition which prevented it from fulfilling the request.", "httpStatus": 406, "detail": "The server encountered an unexpected condition which prevented it from fulfilling the request.", "problemInstance": "urn:ocrmod:/OnDemand/user/Rest/Latest/describe", "errorCode": "GENERIC_INTERNAL_ERR" } ] }

Here is the documentation that we are trying to follow

https://docs.oracle.com/cd/E56321_01/books/OnDemRestAPI/RestAPI_Ref30.html#wp1035687