I have the same issue as this post in Spanish on Linux Mint 18.2 Cinnamon Edition:
E: The repository 'https://s3-us-west-2.amazonaws.com/brave-apt sonya Release' does not have a Release file. N: Updating from such a repository can't be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details
EDIT: I’m also getting a secondary error from the Update Manager:
Failed to fetch https://s3-us-west-2.amazonaws.com/brave-apt/dists/sonya/main/binary-amd64/Packages 403 ForbiddenSome index files failed to download. They have been ignored, or old ones used instead.
I already had
lsb-release installed, so I installed
lsb-core but it made no difference.
deb [arch=amd64] https://s3-us-west-2.amazonaws.com/brave-apt sonya main