Try fully restarting WSL by running wsl --shutdown. This will close all your terminal windows. Then just restart wsl in your terminal.
Please keep in mind that this will also end any process you might have running in other WSL distros.
If that is currently not an option, you may try wsl -t nixos, which will just stop the nixos distro.
(You may need to change that if you imported the distro under some other name). However, some issues will only be resolved after a full restart of WSL.