stash: Error message when I press space over a stash line in status window

[babusri]

When I press SPC on a stash I get

Changes from st...@{0}^2^ to st...@{0}
fatal: ambiguous argument 'st...@0^2^..stash@0': unknown revision or
path not in the working tree.
Use '--' to separate paths from revisions

What does it mean?
I ran "git stash list" and "git stash apply" and it worked fine.