You see Missing or Invalid sellerId parameter when the Seller ID is missing in the formula. You can either type it as text/string in the formula, or type it in a cell and then in the formula use that cell as a reference.
Let’s say that you typed your Seller ID Toy Store in Cell A1, and you want to use GORILLA_SKULIST function, you can use =GORILLA_SKULIST($A$1).
You can also use the formula in this format, =GORILLA_SKULIST(“Toy Store”)