Cannot read findById of underfined in Mongoose

Question

When I call the function, I getting TypeError: Cannot read property 'findById' of undefined

Any help will be really appreciated

Here is the code.

exports.getProductSellingPrice = async (productId) => {
  const product = await Product.findById(productId).select("sellingPrice -_id");
  return Number(product.sellingPrice);
};

Using the intellisense it can show that the Product is imported well

However, when I run the code I am getting the error

    TypeError: Cannot read property 'findById' of undefined

      31 |
      32 | exports.getProductSellingPrice = async (productId) => {
    > 33 |   const product = await Product.findById(productId).select("sellingPrice -_id");
         |                                 ^
      34 |   return Number(product.sellingPrice);
      35 | };
      36 |

      at Object.findById [as getProductSellingPrice] (src/database/services/user.js:33:33)
      at model.getProductSellingPrice [as addProductsToCart] (src/database/models/user.js:48:43)
      at Object.addProductsToCart (tests/models/user.test.js:94:24)
          at runMicrotasks (<anonymous>)