As mentioned by others the error may occur if the url is wrong.
However, the error may also occur if the repo is a private repo and you do not have access or wrong credentials.
Instead of
git clone https://github.com/NAME/repo.git
try
git clone https://username:password@github.com/NAME/repo.git
You can also use
git clone https://username@github.com/NAME/repo.git
and git will prompt for the password (thanks to leanne for providing this hint in the comments).