diff --git a/.github/workflows/server-tests-mariadb.yml b/.github/workflows/server-tests-mariadb.yml
index e3b92fd2699..ed731b8a31f 100644
--- a/.github/workflows/server-tests-mariadb.yml
+++ b/.github/workflows/server-tests-mariadb.yml
@@ -120,7 +120,7 @@ jobs:
           FRAPPE_BRANCH: ${{ github.event.inputs.branch }}
 
       - name: Run Tests
-        run: cd ~/frappe-bench/ && bench --site test_site run-parallel-tests --app erpnext --use-orchestrator --with-coverage
+        run: 'cd ~/frappe-bench/ && bench --site test_site run-parallel-tests --app erpnext --with-coverage --total-builds 4 --build-number ${{ matrix.container }}'
         env:
           TYPE: server
           CI_BUILD_ID: ${{ github.run_id }}
diff --git a/erpnext/stock/doctype/item/item.py b/erpnext/stock/doctype/item/item.py
index c8bb1b960eb..20bc9d9b2c9 100644
--- a/erpnext/stock/doctype/item/item.py
+++ b/erpnext/stock/doctype/item/item.py
@@ -232,10 +232,10 @@ class Item(Document):
 
 	def clear_retain_sample(self):
 		if not self.has_batch_no:
-			self.retain_sample = None
+			self.retain_sample = False
 
 		if not self.retain_sample:
-			self.sample_quantity = None
+			self.sample_quantity = 0
 
 	def add_default_uom_in_conversion_factor_table(self):
 		if not self.is_new() and self.has_value_changed("stock_uom"):
diff --git a/erpnext/stock/doctype/item/test_item.py b/erpnext/stock/doctype/item/test_item.py
index e35c8bf335e..0c710b0ef4b 100644
--- a/erpnext/stock/doctype/item/test_item.py
+++ b/erpnext/stock/doctype/item/test_item.py
@@ -717,8 +717,8 @@ class TestItem(FrappeTestCase):
 
 		item.has_batch_no = None
 		item.save()
-		self.assertEqual(item.retain_sample, None)
-		self.assertEqual(item.sample_quantity, None)
+		self.assertEqual(item.retain_sample, False)
+		self.assertEqual(item.sample_quantity, 0)
 		item.delete()
 
 	def consume_item_code_with_differet_stock_transactions(