The option `services.xserver.displayManager.sddm.package` does not exist

[sedrubal]

I tried to rebuild my OS and got this error message:

error:
       … while calling the 'seq' builtin

         at /nix/store/jp7nlmyb8hwhf3d11s5ylkry7kv4bncv-source/lib/modules.nix:320:18:

          319|         options = checked options;
          320|         config = checked (removeAttrs config [ "_module" ]);
             |                  ^
          321|         _module = checked (config._module);

       … while calling the 'throw' builtin

         at /nix/store/jp7nlmyb8hwhf3d11s5ylkry7kv4bncv-source/lib/modules.nix:296:18:

          295|                     ''
          296|             else throw baseMsg
             |                  ^
          297|         else null;

       error: The option `services.xserver.displayManager.sddm.package' does not exist. Definition values:
       - In `/nix/store/xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-source/configuration.nix':
           {
             _type = "if";
             condition = true;
             content = <derivation sddm-unstable-2023-12-29>;
           }

I'm not sure, how I can fix this. But as it worked before, I assume, it's some broken dependency?

[K900]

Use the latest version of nixos-unstable.

[sedrubal]

I see, thank you!