Discord REST API get channel members

Question

I build my python script, which check users in voice channel.

It's simply build for discord library like this:

client.get_guild(guild_id).get_channel(channel_id).members

and it's return all members is connected to the voice channel:

[<Member id=0 name='name' global_name='name' bot=False nick=None guild=<Guild id=0 name='name' shard_id=0 chunked=True member_count=1>>]

I try this with REST API:

import requests
import os
TOKEN = os.getenv("DISCORD_TOKEN")

header = {
    'Content-Type': 'application/x-www-form-urlencoded',
    'Authorization': 'Bot '+TOKEN
    }

r = requests.get('https://discord.com/api/v9/guilds/guild_id/channels/channel_id/members',headers=header)
print(r.text)

But "members" is not exists in "channels":

{"message": "404: Not Found", "code": 0}

How I get list of members in the voice channel with REST API?

I used bot token and user token, but I not found how solve this problem.

There is REST API documentation about guild members: https://www.postman.com/discord-api/workspace/discord/request/23484324-60127e09-9e0d-4ce6-b905-c8ee6405a225

But nothing about channel's members.