I am unable to send message to multiple users. If i want to send message to multiple users, which users channel access token has to be used in the header?

Question

when i send message to multiple users, it goes to only one user not others. please help me.

API :https://api.line.me/v2/bot/message/multicast
Headers 
Authorization: Bearer yNUK0457INhnn50f9Z9BFPIAJJNd28DWzDlHDDheMegGIyrN0yatLgN19x+vV9VYVxVKLMMsl9qXA1x5D41DUTbDf1RyEm9OBl5eoM4KFs3Jp+Kz7jwZOinnx7gmXL7c4b1jS6HHSJ2TNmJHTEbErAdB04t89/1O/w1cDnyilFU=,SYJdh/KQT1X64qtzKdCtoXlqDlp45iVbbCqwfyKrGeCg/gNGVpf0Iga/sPdZTMbC1CgsukuLMoz1II200gw+8xqTDMRDECw3nr1WieM+eDFsj6IaBeO4g+mPXqH3VNz1hGk0ARv2Egh0x9tPQqFYGQdB04t89/1O/w1cDnyilFU=  
Content-Type:application/json
Body:
{
    "to": ["U9de0102ab382c20d995147ac87c78403","U5f9a61f47f6b71696b49a7f86951d876"],
    "messages":[
        {
            "type":"text",
            "text":"Hello, world10"
        },
      	{
            "type":"text",
            "text":"Hello, world11"
        }
    ]
}

Message is going to this user only "U9de0102ab382c20d995147ac87c78403" . it doesnt go to "U5f9a61f47f6b71696b49a7f86951d876" . please check it and help me.

Ramasamy · Answer

if we send the message to multiple users, In authorization header which users access token has to pass?

Shoya Shiraki · Answer

What is the received response body ?
and if user unfollow bot, cannot send message.

You may want to check userId using profile api.
https://developers.line.me/en/reference/messaging-api/#get-profile

Q&A

I am unable to send message to multiple users. If i want to send message to multiple users, which users channel access token has to be used in the header?