error 404 - not_found for client.CollaborationsManager.GetCollaborationAsync

hello,

 I have .net application that needs to get the collaborators for a file. Working with SDK APIs and hence using the BoxClient. the API I am using to get the collaborators is client.CollaborationsManager.GetCollaborationAsync. However I am getting the error 404. I checked the ID passed to the method do exist. here is the complete Error returned.

"{\"type\":\"error\",\"status\":404,\"code\":\"not_found\",\"context_info\":{\"errors\":[{\"reason\":\"invalid_parameter\",\"name\":\"collab\",\"message\":\"Invalid value '699430145416'. 'collab' with value '699430145416' not found\"}]},\"help_url\":\"http:\\/\\/developers.box.com\\/docs\\/#errors\",\"message\":\"Not Found\",\"request_id\":\"huc997ghmx5v0aei\"}".

I checked from the API reference where we can "Try the API" on the website. Even there too I get the same error.

{
  "type": "error",
  "status": 404,
  "code": "not_found",
  "context_info": {
    "errors": [
      {
        "reason": "invalid_parameter",
        "name": "collab",
        "message": "Invalid value '1***phone number removed for privacy***'. 'collab' with value '1***phone number removed for privacy***' not found"
      }
    ]
  },
  "help_url": "http://developers.box.com/docs/#errors",
  "message": "Not Found",
  "request_id": "aqebnkghmz1dufhh"
}

I have two Apps in my box account and I tried creating the boxclient with both clientid&secretid but did not help.

Any help will be greatly appreciated.

Thanks