The business in 2021 was not invoiced, and it can be invoiced again in May or June of 2022. The invoices for the next year are not recorded in the corresponding year, and if you want to make a deduction before tax, you need to be approved by the tax office. If you have declared the uninvoiced income, and have paid taxes, you can not invoice, or invoice to the customer, the customer to bear the part of the duplicated income tax. Of course, if you have not declared the income, not invoiced to the other party, then the other party can report the behavior, belonging to the tax evasion behavior?