deno check does not accept noImplicitReturns

hello. i have the following config inside

deno.json

deno.json

{
  "compilerOptions": {
    "strict": true,
    "noImplicitReturns": true
  },
  ...
}

{
  "compilerOptions": {
    "strict": true,
    "noImplicitReturns": true
  },
  ...
}

running

deno check

deno check

still allows function signatures without the return type. how can i enforce the

deno check

deno check

to fail if no return type is present?