I have this error when deploying a service in net 9
i have two keys
NIXPACKSCSHARPSDK_VERSION =>9.0.1
_CSHARPSDKVERSION => 9.0.1

error:
… while calling the 'derivationStrict' builtin
at :34:12:
33|
34| strict = derivationStrict drvAttrs;
| ^
35|
… while evaluating derivation '5148520bfab61f99fd25fb9ff7bfbb50dad3c9db-env'
whose name attribute is located at /nix/store/lgcjj6s23v2203zyihsd0j26wh1saj0c-source/pkgs/stdenv/generic/make-derivation.nix:300:7
… while evaluating attribute 'passAsFile' of derivation '5148520bfab61f99fd25fb9ff7bfbb50dad3c9db-env'
at /nix/store/lgcjj6s23v2203zyihsd0j26wh1saj0c-source/pkgs/build-support/trivial-builders/default.nix:88:7:
87| inherit buildCommand name;
88| passAsFile = [ "buildCommand" ]
| ^
89| ++ (derivationArgs.passAsFile or []);
(stack trace truncated; use '--show-trace' to show the full, detailed trace)
error: undefined variable 'dotnet-sdk9' at /app/.nixpacks/nixpkgs-5148520bfab61f99fd25fb9ff7bfbb50dad3c9db.nix:19:9: 18| '') 19| dotnet-sdk9
| ^
20| ];

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