Correction Invoice is not linked to Original Invoice!

What causes this issue?

It is not possible to add new items or delete current ones on Correction
Tax Invoices without link to Tax Invoice.

System Response

It is not possible to add or delete items on Correction Tax Invoice
without link to original Tax Invoice.

How to fix this error?

Please, switch to tab @3P@ <ZH>General data</> add fill in field <ZH>Tax
Invoice Number</> in part Invoice Identification.
If it is new Correction Invoice, you have to <ZH>Save</> it first by
clicking on @2L@ button or by pressing <ZH>Ctrl + S</>.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.