What is the 5 1 invoice sent by SMS?

A software based on invoice collaboration. It can conveniently manage invoice information and provide a variety of convenient invoicing methods, such as scanning code invoicing and manual entry invoicing. You can use 5 1 invoice to query, issue, upload and manage invoices, and support a variety of invoice formats and methods to help manage invoice information more conveniently. If the 5 1 invoice is not used, the message may be fraudulent information. Don't click on the link or download the attachment, so as to avoid economic losses or disclosure of private information.