I noticed that the specification of Files: copy in Drive API was changed. About the method of Files: copy in Drive API v3, this method could be used with the scope of https://www.googleapis.com/auth/drive.readonly until July 5, 2020. But I confirmed that in the current stage, the scope is required to be changed to the following scopes.
https://www.googleapis.com/auth/drivehttps://www.googleapis.com/auth/drive.filehttps://www.googleapis.com/auth/drive.appdatahttps://www.googleapis.com/auth/drive.photos.readonly
Please be careful this.