Error, nonexistant file in nixos-rebuild switch

Help
1

For about a month now, sudo nixos-rebuild switch --upgrade results in:

error: getting attributes of path '/nix/store/5az44ijj2q2rscjby74nksrb6d58i2s4-firewall-start': No such file or directory

How can I go about solving this?

Thanks!

2

I tried doing sudo nix-store -r /nix/store/5az44ijj2q2rscjby74nksrb6d58i2s4-firewall-start and am now getting the same error about a different file. nix-store -r doesn’t help anymore:

error: getting attributes of path '/nix/store/1b7zz0f7w0l4ahag0krw5qylcfvrdd4f-local-cmds': No such file or directory