fatal: ambiguous argument 'HEAD~6'

giraffelife

fatal: ambiguous argument 'HEAD~6': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'

This means you have gone back more than the total number of commits you have, see the commits by running:

$ git log --oneline