As per the recent process, it is required that sellers meet all the Amazon requirements. It is important to get your invoices screened before sending them. Amazon generally asks for invoices to authenticate a seller and their products. The frequency of invoice requests has increased in recent times. Any discrepancies in the supply chain documentation may lead to even the blocking of the account.
Amazon is one of the topmost online marketplaces, has to maintain its integrity by inhibiting fraud sellers on their platform. If you are a new seller, then this step will be taken to find out if you are a legitimate seller or not. If you are an existing seller, Amazon may ask for invoice verification following some constant complaints by the buyers.