Activity changes update the last_update field of the Prospect

biz/models.py

@@ -144,6 +144,11 @@ class Activity(BaseModel):
     def delete_dependencies(self):
         pass
 
+    def save(self, *args, **kwargs):
+        super().save(*args, **kwargs)
+        # Update last_update for all related prospects when activity is saved
+        self.prospects.update(last_update=timezone.now())
+
     class Meta:
         verbose_name_plural = "Activities"
         ordering = ['-creation_date']