The example code produces an NullReferenceException

[peckebrecht]

I used the example code from the README in an .NET 8.0 test project and it produces an NullReferenceException on Save. I can't tell what's null here.

System.NullReferenceException: Object reference not set to an instance of an object.

Stack Trace: 
InvoiceDescriptor23CIIWriter.Save(InvoiceDescriptor descriptor, Stream stream, ZUGFeRDFormats format)
InvoiceDescriptor23Writer.Save(InvoiceDescriptor descriptor, Stream stream, ZUGFeRDFormats format)
InvoiceDescriptor.Save(Stream stream, ZUGFeRDVersion version, Profile profile, ZUGFeRDFormats format)

[stephanstapel]

Do you know in which line the exception is thrown?

[peckebrecht]

No.

[stephanstapel]

I am afraid that I can't help if you can't provide additional information

[peckebrecht]

I just wanted to help with a bug report.