How can I set the date type with create.indices in elasticsearch?

[securisec (Securisec CTF)]

I am having trouble setting the date type specially for nested objects in elasticsearch withe nodejs. The data field in my example holds the time in epoch in seconds. I am using the create.indices endpoint along with the bulk endpoint sod that I can set my own _id value. I am not even getting the prompt in Kibana that usually asks me to select which fields are type date.

The issue I am having is that the date time is always being set to number or long when I try to check the data in Kibana. I am following the docs but cant figure out what I am doing wrong..

How can I create the indices so that the date type is set properly?

const { Client } = require('@elastic/elasticsearch');
const client = new Client({ node: 'http://localhost:9200' });

client.indices
	.create(
		{
			index: 'test',
			body: {
				mappings: {
					properties: {
						hello: { type: 'text' },
						some: { data: { type: 'date' } }
					}
				}
			}
		},
		{ ignore: [400] }
	)
	.then(() => {
		let data = [{ hello: 'world', some: { data: 1579895431 } }];
		let body = data.flatMap((doc) => [
			{ index: { _index: 'test', _id: '123id' } },
			doc
		]);
		console.log(body);
		client
			.bulk({ refresh: true, body })
			.then((res) => {
				console.log(res);
			})
			.catch((error) => console.log(error));
	})
	.catch(console.log);