ElasticSearch dynamic_date_formats is not applied if there is a mapping created with the index

gistfile1.sh

curl -XDELETE "http://localhost:9200/myindex"

curl -XPOST "http://localhost:9200/myindex/" -d '
{
  "state": "open",

  "mappings": {
    "message": {
      
    }
  }
}'

curl -XPOST "http://localhost:9200/myindex/_mapping/message" -d '
{
  "message": {
    "dynamic_templates": [],
    "dynamic_date_formats": [
      "dd.MM.yyyy"
    ],
    "properties": {
      "myfield": {
        "type": "string"
      }
    }
  }
}'

curl -XDELETE "http://localhost:9200/myindex"

curl -XPOST "http://localhost:9200/myindex/"

curl -XPOST "http://localhost:9200/myindex/_mapping/message" -d '
{
  "message": {
    "dynamic_templates": [],
    "dynamic_date_formats": [
      "dd.MM.yyyy"
    ],
    "properties": {
      "myfield": {
        "type": "string"
      }
    }
  }
}'