Aggregating on a nested field

I have an elastic search schema as below.

{
  "mappings": {
    "properties": {
      "process_id": {
        "type": "keyword"
      },
      "user_info": {
        "type": "nested",
        "properties": {
          "first_name": {
            "type": "text",
            "fields": {
              "keyword": {
                "type": "keyword",
                "ignore_above": 256
              }
            }
          },
          "last_name": {
            "type": "text",
            "fields": {
              "keyword": {
                "type": "keyword",
                "ignore_above": 256
              }
            }
          },
          "place": {
            "type": "text",
            "fields": {
              "keyword": {
                "type": "keyword",
                "ignore_above": 256
              }
            }
          }
      

2. I have added the below documents to the index.

POST processes/_bulk 
  {"index":{"_id":1}}
{"process_id": "123", "user_info": [{"first_name": "A", "last_name": "B","place":"London"},{"first_name": "C", "last_name": "D","place":"Moscow"}]}
{"index":{"_id":2}}
{"process_id": "123", "user_info": [{"first_name": "C", "last_name": "B","Place":"Delhi"},{"first_name": "A", "last_name": "D","Place":"Bangalore"}]}

3. I wanted to search for process_id as 123, first_name as A and last_name as B, and and aggregate on Place of the user_info. I am trying to do it as below.

{   "query": {
    "bool": {
      "must": [
        {
          "query_string": {
            "query": "process_id:123"
          }
        },
        {
          "nested": {
            "path": "user_info",
            "query": {
              "query_string": {
                "query": "user_info.first_name:A AND user_info.last_name:B"
              }
            }
          }
        }
      ]
    }   },   "aggs": {
    "user_info": {
      "nested": {
        "path": "user_info"
      },
      "aggs": {
        "user_info.place": {
          "terms": {
            "field": "user_info.place"
          }
        }
      }
    }   } }

The result returns the first document correctly. However, the aggregate on the field place returns both London and Moscow. However, I want London to be returned as the output. I am not sure how to proceed with this. I have tried Nested Filter Search Aggregation as well but no success on the same.

Hello,
You need to apply filter aggregation on nested level to sweep Moscow out.

Can you please elaborate a bit more?

Pls check

thank you! It worked