Cannot create new index/template with geo-point field?

[rhc17 (Ray)]

Hi, new to this and have been wrestling with this for the past few days. I am trying to get a Logstash .csv import to Elasticsearch to work correctly, but am running into trouble with getting my geo-point field in.
Specifically, the error I am getting is:

            {
              "error": {
                "root_cause": [
                  {
                    "type": "illegal_argument_exception",
                    "reason": "Rejecting mapping update to [my-index-name] as the final mapping would have more than 1 type: [_doc, node_points]"
                  }
                ],
                "type": "illegal_argument_exception",
                "reason": "Rejecting mapping update to [my-index-name] as the final mapping would have more than 1 type: [_doc, node_points]"
              },
              "status": 400
            }

The ES index I am trying to use is (note I have also tried creating a template to accomplish this, yes matching my index names exactly, and still getting the same error) :

PUT /my-index-name
{
  "settings" : {
        "index.number_of_shards" : 1
    },
    "mappings" : {
        "_doc" : {
            "properties" : {
                "location" : { "type" : "geo_point"}
            }   
        }
    }
} 

Logstash config:

input {
  file {
      mode => "read"
      path => ["C:/logstash-6.4.2/sample/*.csv"]
      start_position => "beginning"
    #  delimiter => "\n"
      file_chunk_size => 1048576
      file_completed_log_path => "C:\logstash-6.4.2\sample\filelog.txt"
      file_completed_action => "log"
      sincedb_path => "NUL"
  }
}
filter {
    csv {
        separator => ","
        columns => ["fieldname1",... ]
        convert => {
            "fieldname1" => "float"
            …. #lots of these
          "QuadBinLong_Lat_Deg" => "float"
          "QuadBinLong_Lon_Deg" => "float" 
        }
    }
    mutate { add_field => { "datetime" => "%{SystemTime_Date}%{SystemTime_Local}" } }
    date {
        match => ["datetime","yyyyMMddHHmmss.SSS","yyyMMddHHmmss.SS"]
        remove_field => ["datetime"]
    }

    mutate { rename => {"QuadBinLong_Lat_Deg" => "[location][lat]"} }
    mutate { rename => {"QuadBinLong_Lon_Deg" => "[location][lon]"} }
    mutate { remove_field => ["message"] }
}
output {
  elasticsearch {
    hosts => ["http://localhost:9200"]
    index => "my-index-name"
    template => "C:\elastic\mytemplate.json"

  }
   stdout { codec => rubydebug}
}

I have made sure to delete the index every time before running Logstash, but the same error returns. I think I am missing something in the creation of the index/template, but am not sure what. The goal is to load a ton of numeric data, set the @timestamp field to a concatenation of stored date & time data, and get the two latitude and longitude fields into an elasticsearch geo-point format. I should be able to make both maps and time series visualizations from this data set, but at the moment cannot seem to do either.