What does the yellow, blue and red of the billing system mean?
Under normal circumstances, the invoice is a "blue ticket". If there is a return or an incorrect invoice, a "red ticket" should be issued to offset the current sales income (drawer). If you need to issue a new invoice, just issue the correct invoice. This refers to the ordinary invoice. If it is a special value-added tax invoice, if it fails to pass the certification in the current month, a negative (scarlet letter) invoice can be issued to deduct the current sales; If the same certification is passed, the buyer's tax bureau needs to issue a notice of issuing red-ink invoices, and the seller can issue red-ink (negative) invoices with this notice.