In Zhumadian, Henan Province, I bought a machine and didn't call the national tax department for 12366 to complain. As a kind of shopping voucher, invoice is an important evidence with legal effect for consumers to safeguard their legitimate rights and interests. Once consumers are careless or careless when shopping, their interests may be damaged and they cannot be compensated. Therefore, when shopping, consumers should not only ask for invoices according to law and keep them properly, but also pay attention to whether the invoices are formal to protect their legitimate rights and interests. It is wrong for business premises not to issue invoices to consumers. For those who refuse to invoice, consumers can call the national tax department at 12366 to complain.