Unable to save sales invoice

Getting following error when trying to create sales invoice. Any solution for this error

some ideas what to look for.

  • is this a new Invoice, or are you trying to save an existing Invoices which has not been “Submitted” yet, after making a change or does that happen on the first save attempt when after you opened a “New Sales Invoice”?
  • does the ERPNext user have sufficient permissions to create Invoices?
  • Can you locate the Invoice in the “Sales Invoice List”

It is new invoice
Even it doesn’t work after changing naming series.
User has administrative permissions.
Invoice doesn’t exit

I am facing this issue after restoring the backup

the fact that it is a new invoice and at the same time the error message mentions SINV/0519/29 is suspicious.
A new (not yet saved invoice) does not have any number yet. It is being created upon saving.

If you haven’t much work after the restore I’d probably try to restore it once again (maybe at first in a testing instance) and see whether it does any good in this regards.