How to discard the Duplicate values in ElasticSearch using DSL Query?

Here I am trying to get the attribute_name on the basis of query customer the Problem here is there is lots of duplicate value in attribute name which I want to discard , can someone pls help me with this

 {
  "_source": [
    "attribute_name"
  ],
  "size": 500, 
  "query": {
    "multi_match": {
      "query": "CUSTOMER",
      "fields": [
        "hierarchy_name",
        "attribute_name"
      ]
    }
  }
}

LIke suppose this is my output , here I want to discard duplicate attribute_name

 {
        "_index": "planlytx_records",
        "_type": "_doc",
        "_id": "tD6WDnkBQTXQIneq8Ypr",
        "_score": 2.5454113,
        "_source": {
          "attribute_name": "CUSTOMER"
        }
      },
      {
        "_index": "planlytx_records",
        "_type": "_doc",
        "_id": "3j6WDnkBQTXQIneq8Yps",
        "_score": 2.5454113,
        "_source": {
          "attribute_name": "CUSTOMER"
        }
      },
      {
        "_index": "planlytx_records",
        "_type": "_doc",
        "_id": "nT6WDnkBQTXQIneqyonu",
        "_score": 1.8101583,
        "_source": {
          "attribute_name": "REGION"
        }
      },
      {
        "_index": "planlytx_records",
        "_type": "_doc",
        "_id": "6D6WDnkBQTXQIneq8Yps",
        "_score": 1.8101583,
        "_source": {
          "attribute_name": "REGION"
        }
      },

Myoutput should be something like this ..

{
        "_index": "planlytx_records",
        "_type": "_doc",
        "_id": "3j6WDnkBQTXQIneq8Yps",
        "_score": 2.5454113,
        "_source": {
          "attribute_name": "CUSTOMER"
        }
      },
      {
        "_index": "planlytx_records",
        "_type": "_doc",
        "_id": "nT6WDnkBQTXQIneqyonu",
        "_score": 1.8101583,
        "_source": {
          "attribute_name": "REGION"
        }
      },

You can use collapse parameter, to remove duplicate from your search result based on field value

Adding a working example with index data, mapping, search query and search result

Index Mapping:

{
  "mappings": {
    "properties": {
      "attribute_name": {
        "type": "text",
        "fields": {
          "keyword": {
            "type": "keyword"
          }
        }
      }
    }
  }
}

Index Data:

{
  "attribute_name": "CUSTOMER-ALL"
}
{
  "attribute_name": "CUSTOMER-ALL"
}
{
  "attribute_name": "CUSTOMER"
}
{
  "attribute_name": "CUSTOMER"
}

Search Query:

{
  "query": {
    "multi_match": {
      "query": "CUSTOMER",
      "fields": [
        "attribute_name"
      ]
    }
  },
  "collapse": {
    "field": "attribute_name.keyword"
  }
}

Search Result:

 "hits": [
      {
        "_index": "67260491",
        "_type": "_doc",
        "_id": "1",
        "_score": 0.12199639,
        "_source": {
          "attribute_name": "CUSTOMER"
        },
        "fields": {
          "attribute_name.keyword": [
            "CUSTOMER"
          ]
        }
      },
      {
        "_index": "67260491",
        "_type": "_doc",
        "_id": "3",
        "_score": 0.09271726,
        "_source": {
          "attribute_name": "CUSTOMER-ALL"
        },
        "fields": {
          "attribute_name.keyword": [
            "CUSTOMER-ALL"
          ]
        }
      }
    ]

Update 1:

If you just want to delete the duplicate data, you can run the below query

{
  "collapse": {
    "field": "attribute_name.keyword"
  }
}

Search Result will be

"hits": [
      {
        "_index": "67276433",
        "_type": "_doc",
        "_id": "1",
        "_score": 1.0,
        "_source": {
          "attribute_name": "CUSTOMER"
        },
        "fields": {
          "attribute_name.keyword": [
            "CUSTOMER"
          ]
        }
      },
      {
        "_index": "67276433",
        "_type": "_doc",
        "_id": "3",
        "_score": 1.0,
        "_source": {
          "attribute_name": "REGION"
        },
        "fields": {
          "attribute_name.keyword": [
            "REGION"
          ]
        }
      }
    ]