NestJS GraphQL - call ResolveField() in nested fields

I have a question about how to call @ResolveField() category when it is in payload?

getProducts(controls: $controls) {
  count
  payload {
    id
    name
    category {
      name
    }
  }
}

I'm confused here (code below doesn't work):

// I need something like @ResolveField('payload.category', ...) 
@ResolveField('name', () => TypeFunc);
async getCategory(@Parent() product: Product) {
  return this.categoryService.getCategory(product.id);
}