LINE WORKS

I am testing the Line works API https://www.worksapis.com/v1.0/monitoring/message-contents/download by postman by following the guide https://qiita.com/mmclsntr/items/eee8d8f3546410fe6652 .

I have the service account and get the bearer token with permission scope "monitoring.read audit.read file.read bot.read bot contact contact.read", I am able to get right response by the api {{baseUrl}}/users/:userId?userId=steven.liang.

but the message content download api keeps responding “ 401Unauthorized ” error, I did n't know where the root cause is since I already have the “ monitoring.read ” permission by service account. Can you pls give me some hint how to fix this issue?

Many thanks for your help in advance.