diff --git a/taxes_az/taxes_az/doctype/vat_allocation/vat_allocation.json b/taxes_az/taxes_az/doctype/vat_allocation/vat_allocation.json
index 25cbe3a..bcfab92 100644
--- a/taxes_az/taxes_az/doctype/vat_allocation/vat_allocation.json
+++ b/taxes_az/taxes_az/doctype/vat_allocation/vat_allocation.json
@@ -1,6 +1,5 @@
 {
  "actions": [],
- "autoname": "format:VAT-{year}-{month}",
  "creation": "2025-09-29 19:03:22.767217",
  "doctype": "DocType",
  "engine": "InnoDB",
@@ -240,7 +239,6 @@
  "modified_by": "Administrator",
  "module": "Taxes Az",
  "name": "VAT allocation",
- "naming_rule": "Expression",
  "owner": "Administrator",
  "permissions": [
   {
diff --git a/taxes_az/taxes_az/doctype/vat_allocation/vat_allocation.py b/taxes_az/taxes_az/doctype/vat_allocation/vat_allocation.py
index af10490..f295821 100644
--- a/taxes_az/taxes_az/doctype/vat_allocation/vat_allocation.py
+++ b/taxes_az/taxes_az/doctype/vat_allocation/vat_allocation.py
@@ -8,6 +8,27 @@ import json
 ROUNDING_TOLERANCE = Decimal('0.01')
 
 class VATallocation(Document):
+    def autoname(self):
+        """
+        Generate unique name for the document
+        - For submitted documents or first draft: VAT-{year}-{month}
+        - For additional drafts: VAT-{year}-{month}-{counter}
+        """
+        if not self.year or not self.month:
+            frappe.throw(_("Year and Month are required"))
+
+        base_name = f"VAT-{self.year}-{self.month}"
+
+        # Check if base name already exists
+        if frappe.db.exists('VAT allocation', base_name):
+            # Add counter for additional drafts
+            counter = 1
+            while frappe.db.exists('VAT allocation', f"{base_name}-{counter}"):
+                counter += 1
+            self.name = f"{base_name}-{counter}"
+        else:
+            self.name = base_name
+
     def validate(self):
         # Check if document with same year and month already exists
         self.validate_unique_year_month()