Digital signature upload failed, system failure. The specific reasons for the failure of Zhu Ying Bank's invoicing are as follows:

1. In the process of uploading invoices through the network and adding digital signatures to electronic invoices, the tax digital certificate will become invalid.

2. The failure of the tax bureau's signing and inspection system will also lead to the failure of signing and inspection. These are caused by non-human factors, which are rare but inevitable. Failed invoices must be voided and reissued, and cross-month invoices need to be reissued by the tax bureau stub.