diff --git a/internal/modules/master/phase-activities/services/phase-activity.service.go b/internal/modules/master/phase-activities/services/phase-activity.service.go
index 1c6b15ce..c34e6a31 100644
--- a/internal/modules/master/phase-activities/services/phase-activity.service.go
+++ b/internal/modules/master/phase-activities/services/phase-activity.service.go
@@ -110,6 +110,17 @@ func (s *phaseActivityService) CreateOne(c *fiber.Ctx, req *validation.Create) (
 		return nil, fiber.NewError(fiber.StatusBadRequest, "time_type cannot be empty")
 	}
 
+	existing, err := s.Repository.First(c.Context(), func(db *gorm.DB) *gorm.DB {
+		return db.Where("phase_id = ? AND name = ? AND time_type = ?", phase.Id, name, timeType)
+	})
+	if err != nil && !errors.Is(err, gorm.ErrRecordNotFound) {
+		s.Log.Errorf("Failed to check phaseActivity uniqueness: %+v", err)
+		return nil, err
+	}
+	if existing != nil {
+		return nil, fiber.NewError(fiber.StatusBadRequest, "phase activity with same name and time_type already exists")
+	}
+
 	createBody := &entity.PhaseActivity{
 		PhaseId:     phase.Id,
 		Name:        name,