Getting a 5461 error when trying to List a generic product.

Hello, I’m trying to create a dummy listing to make sure my product will be able to sell on Amazon. While creating the listing under generic I keep getting a error code. Could this be due to my UPC codes I’m trying to use? We are going to brand the product but don’t actually have the packaging and branding on the product yet. That is why we are using the title generic for the time being. Any help or advice would be greatly appreciated! Thank you