Fatal: could not read Username for 'https://github.com'

Adding a repository in HACs:

https://github.com/blakeblackshear/frigate-hass-addon

and getting an error

21-10-14 14:48:21 ERROR (MainThread) [supervisor.store.git] Can't clone https://github.com/blakeblackshear/frigate-hass-addon repository: Cmd('git') failed due to: exit code(128)
  cmdline: git clone -v --recursive --depth=1 --shallow-submodules https://github.com/blakeblackshear/frigate-hass-addon /data/addons/git/3549fbd8
  stderr: 'Cloning into '/data/addons/git/3549fbd8'...
fatal: could not read Username for 'https://github.com': No such device or address

any ideas?!