Невозможно установить Heroku

Я пытаюсь установить Heroku на Ubuntu 16.04, следуя инструкциям с официального сайта, но после команды sudo apt-get update Я получаю следующие ошибки:

Err:30 https://cliassets.heroku.com/branches/stable/apt ./ Packages SSL: certificate subject name (*.herokuapp.com) does not match target host name 'cliassets.heroku.com'
Ign:31 https://cliassets.heroku.com/branches/stable/apt ./ Translation-en_US
Ign:32 https://cliassets.heroku.com/branches/stable/apt ./ Translation-en
Fetched 4,351 kB in 22s (192 kB/s)
Reading package lists... Done
W: The repository 'https://cliassets.heroku.com/branches/stable/apt ./ Release' does not have a Release file.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: Failed to fetch https://cliassets.heroku.com/branches/stable/apt/ ./ Packages  SSL: certificate subject name (*.herokuapp.com) does not match target host name 'cliassets.heroku.com'
E: Some index files failed to download. They have been ignored, or old ones used instead.

Я просмотрел другие ответы и решения, но не помог. Любая помощь будет оценена.