diff --git a/src/main.py b/src/main.py
index 9ac8e90..6154887 100644
--- a/src/main.py
+++ b/src/main.py
@@ -67,17 +67,16 @@ def main():
         invoice = parse_yaml_file(invoice_file)
         envelope = parse_yaml_file(envelope_file)
 
-        print('Invoice data:')
-        print(invoice)
-
-        print(envelope)
-
         print('Envelope data:')
         envelope_data = DataObject(**envelope)
         print(envelope_data.__dict__)
 
         print('Invoice data:')
         invoice_data = DataObject(**invoice)
+        if not hasattr(invoice_data, 'Id'):
+            invoice_data.Id = None
+
+        invoice_data.Id = invoice_data.Id or invoice_file.stem
         print(invoice_data.__dict__)
 
     except FileNotFoundError as e:
@@ -94,7 +93,10 @@ def main():
     template = generator.prepare_template(invoice_data, envelope_data)
 
     try:
-        html_generator.HtmlTemplate.convert_html_to_pdf(template, 'invoice.pdf')
+        print('Generating invoice...')
+        invoice_pdf = Path(invoice_data.Id).with_suffix('.pdf')
+        print(f'Invoice PDF: {invoice_pdf}')
+        html_generator.HtmlTemplate.convert_html_to_pdf(template, invoice_pdf)
     except Exception as e:
         print(f'Error: {e}')
         return
diff --git a/test_data/RG004711.yaml b/test_data/RG004711.yaml
index 4838742..39f2955 100644
--- a/test_data/RG004711.yaml
+++ b/test_data/RG004711.yaml
@@ -1,3 +1,4 @@
+#Id: RG004712
 CustomerId: KD01234
 #InvoiceDate: 2023-12-23
 
diff --git a/test_data/templates/invoice.html b/test_data/templates/invoice.html
index 96c06ea..2302a1a 100644
--- a/test_data/templates/invoice.html
+++ b/test_data/templates/invoice.html
@@ -42,6 +42,7 @@
         #letter_head_content {
             background-color: lightblue;
         }
+
     </style>
 </head>
 
@@ -57,15 +58,30 @@
 </div>
 <div id="letter_head_content">
     {% for address in envelope.AddressContent.Contents %}
-            {% if address.Head %}
+    {% if address.Head %}
     <p><strong>{{ address.Head }}</strong></p>
-            {% endif %}
+    {% endif %}
     <p>{{ address.Text | replace('\n', '<br>') }}</p>
     {% endfor %}
 </div>
 
 
 <!-- HTML Content -->
+<table>
+    <tr>
+        <td>Rechnungsnummer:</td>
+        <td>Kundennummer:</td>
+        <td>Rechnungsdatum:</td>
+    </tr>
+    <tr>
+        <td>{{ invoice.Id }}</td>
+        <td>{{ invoice.CustomerId }}</td>
+        <td>{{ invoice.InvoiceDate }}</td>
+    </tr>
+    </tr>
+</table>
+
+
 To PDF or not to PDF
 
 <section>