Branded types in typescript

index.ts

export type Branded<T, K extends string = 'BRANDED_TYPE'> = T & { __opaque__?: K };

type Brand = {
 User: Branded<string, 'User'>,
 Product: Branded<string, 'Product'>,
}

function getUser(userId: Brand['User']) {
   // get user
}

const userId: Brand['User'] = '12'
const productId: Brand['Product'] = '34';

getUser('hello') // works
getUser(userId) // works
getUser(productId) // Type '"Product"' is not assignable to type '"User"'