From f622996c486d5ba4f9f5c3916e97fb5fcac34a0c Mon Sep 17 00:00:00 2001
From: Nishka Gosalia <nishkagosalia@Nishkas-MacBook-Air.local>
Date: Fri, 2 Jan 2026 16:50:20 +0530
Subject: [PATCH] fix: disallowing overlapping time logs in allow on submit
 mode

---
 .../projects/doctype/timesheet/test_timesheet.py  | 15 +++++++++++++++
 erpnext/projects/doctype/timesheet/timesheet.py   |  1 +
 2 files changed, 16 insertions(+)

diff --git a/erpnext/projects/doctype/timesheet/test_timesheet.py b/erpnext/projects/doctype/timesheet/test_timesheet.py
index 55d90e85c94..ed815c45884 100644
--- a/erpnext/projects/doctype/timesheet/test_timesheet.py
+++ b/erpnext/projects/doctype/timesheet/test_timesheet.py
@@ -172,6 +172,21 @@ class TestTimesheet(ERPNextTestSuite):
 		settings.ignore_employee_time_overlap = 1
 		settings.save()
 		timesheet.save()  # should not throw an error
+		timesheet.submit()  # should not throw an error
+		settings.ignore_employee_time_overlap = 0
+		settings.save()
+
+		timesheet.append(
+			"time_logs",
+			{
+				"billable": 1,
+				"activity_type": "_Test Activity Type",
+				"from_time": now_datetime(),
+				"to_time": now_datetime() + datetime.timedelta(hours=3),
+				"company": "_Test Company",
+			},
+		)
+		self.assertRaises(frappe.ValidationError, timesheet.submit)
 
 		settings.ignore_employee_time_overlap = initial_setting
 		settings.save()
diff --git a/erpnext/projects/doctype/timesheet/timesheet.py b/erpnext/projects/doctype/timesheet/timesheet.py
index d9ee987c8c2..866281bf1ef 100644
--- a/erpnext/projects/doctype/timesheet/timesheet.py
+++ b/erpnext/projects/doctype/timesheet/timesheet.py
@@ -79,6 +79,7 @@ class Timesheet(Document):
 	def on_update_after_submit(self):
 		self.validate_mandatory_fields()
 		self.update_task_and_project()
+		self.validate_time_logs()
 
 	def calculate_hours(self):
 		for row in self.time_logs: