Doesn't get installed with fisher

[gvlasov-infusemedia]

$ fisher install jorgebucaran/nvm.fish
fisher: unknown flag or command "install"
usage: fisher add <package...>     Add packages
       fisher rm  <package...>     Remove packages
       fisher                      Update all packages
       fisher ls  [<regex>]        List installed packages matching <regex>
       fisher --help               Show this help
       fisher --version            Show the current version
       fisher self-update          Update to the latest version
       fisher self-uninstall       Uninstall from your system
examples:
       fisher add jethrokuan/z rafaelrinaldi/pure
       fisher add gitlab.com/foo/bar@v2
       fisher add ~/path/to/local/pkg
       fisher add <file
       fisher rm rafaelrinaldi/pure
       fisher ls | fisher rm
       fisher ls fish-\*
$ fisher add jorgebucaran/nvm.fish
fetching https://codeload.github.com/franciscolourenco/done/tar.gz/master
fetching https://codeload.github.com/jorgebucaran/nvm.fish/tar.gz/master
fisher: cannot add github.com/jorgebucaran/nvm.fish -- is this a valid package?
linking ~/.config/fish/conf.d/done.fish
updated 1 package in 0.74s

[freaz]

I had the same problem. It helped to me to update Fisher to v4 jorgebucaran/fisher#652

[jorgebucaran]

@gvlasov-infusemedia You appear to be using Fisher 2 or older? Please upgrade to the latest Fisher.