$ nix-env -iA nixos.papirus-icon-theme
error: syntax error, unexpected end of file
at /nix/store/5nfyyvn6zc5nyd4iz67irxx1szaxrhh5-env-manifest.nix:1:1:
im cant rollback because runing the commands
$ nix-env --delete-generations old
$ nix-collect-garbage
how to solve?