Nix flake update results in a public key not valid error

[lcnbr]

When nix flake updateing I am getting this error:

error:
       … while updating the lock file of flake 'git+file:///home/lcnbr/.config/nixos'

       … while updating the flake input 'hardware'

       … while fetching the input 'github:nixos/nixos-hardware'

       error: public key is not valid 

my flake is here: https://github.com/lcnbr/nixosConf/tree/pub_key