On the verification screen, it’s telling me to upload the letter of Authorization:
You don’t need LOA to complete seller account registration.
The Letter of Authorization (LOA) is usually a document that proves you are authorized to operate the seller account on behalf of the registered business. It should include the full registered business name, the primary user’s full name exactly as entered during registration, and a recent issue date (within the last 180 days). This can be a company letter on official letterhead, signed by the business owner, director, or authorized manager, stating that you are permitted to manage and sell on the Amazon account. Make sure the names match exactly with your account details and registration documents.”