Hi @Hiroshi0900
Welcome to the Auth0 Community!
I am sorry about the late reply to your inquiry!
I would recommend to review this community post regarding retrieving the access token and check out our Github documentation for NextJS in order to read more about the handleLogin() function since you might not be passing the correct scopes/audience to your CURL call.
If you have any other questions, feel free to let me know or post again on the community!
Kind Regards,
Nik