I am trying to generate a data warehouse report in adobe analytics using Omniture API 1.4  which will land on FTP server , in our data warehouse portal we have some custom data breakdowns and data metrics .  These are as follows :

Data Breakdowns:Customer ID (v24) (eVar24)                Custom

                               Page URL (v43) (eVar43)                     Custom

                               Mobile Device Type                             Standard

                               App or Web (v9) (SAINT)                     Custom

Data Metrics:        Product Impressions (e3)                    Custom

                              Searches (e1)                                         Custom

When I am using standard Metrics like Orders , Revenue i am able to get report , but when I am putting  above variable in JSON , I am getting an error that these variables are not present. The JSON which I am using is

{

   "reportDescription":{

      "reportSuiteID":"tescoukgroceriesprod",

      "dateFrom":"2018-11-30",

      "dateTo":"2018-12-01",

      "dateGranularity":"day",

      "metrics":[

         {

            "id":"Product Impressions"

         },

         {

            "id":"Searches "

         }

      ],

      "elements":[

         {

            "id":"Customer ID"

         },

         {

            "id":"Page URL"

         },

         {

            "id":"Mobile Device Type"

         },

         {

            "id":"App or Web"

         }

      ],

      "source":"warehouse",

      "ftp":{

         "host":"***********",

         "port":"**",

         "directory":"******",

         "username":"***********",

         "password":"************",

         "filename":"myReport.csv"

      }

   }

}

URL : https://api3.omniture.com/admin/1.4/rest/?method=Report.Queue