fix: incorrect posting time fetching incorrect qty (#29103)

diff --git a/erpnext/stock/utils.py b/erpnext/stock/utils.py
index 3b1ae3b..3c70b41 100644
--- a/erpnext/stock/utils.py
+++ b/erpnext/stock/utils.py
@@ -86,8 +86,8 @@
 
 	from erpnext.stock.stock_ledger import get_previous_sle
 
-	if not posting_date: posting_date = nowdate()
-	if not posting_time: posting_time = nowtime()
+	if posting_date is None: posting_date = nowdate()
+	if posting_time is None: posting_time = nowtime()
 
 	args = {
 		"item_code": item_code,