diff --git a/common/djangoapps/student/signals/signals.py b/common/djangoapps/student/signals/signals.py
index 9e7b7c90e6f778fec357d30e0f424b96320cee85..fe45b92841295eaf8412fda9247c561ba0a2ac9c 100644
--- a/common/djangoapps/student/signals/signals.py
+++ b/common/djangoapps/student/signals/signals.py
@@ -7,4 +7,4 @@ ENROLLMENT_TRACK_UPDATED = Signal(providing_args=['user', 'course_key'])
 UNENROLL_DONE = Signal(providing_args=["course_enrollment", "skip_refund"])
 ENROLL_STATUS_CHANGE = Signal(providing_args=["event", "user", "course_id", "mode", "cost", "currency"])
 REFUND_ORDER = Signal(providing_args=["course_enrollment"])
-SAILTHRU_AUDIT_PURCHASE = Signal(providing_args=["event", "user", "course_id", "mode"])
+SAILTHRU_AUDIT_PURCHASE = Signal(providing_args=["user", "course_id", "mode"])
diff --git a/lms/djangoapps/commerce/api/v0/views.py b/lms/djangoapps/commerce/api/v0/views.py
index 5ca26fabc5328af02a76ce191f259f2785fe3c87..e02e971de7b9af5785bf67ccc742540c2b53edfb 100644
--- a/lms/djangoapps/commerce/api/v0/views.py
+++ b/lms/djangoapps/commerce/api/v0/views.py
@@ -143,7 +143,7 @@ class BasketsView(APIView):
             self._enroll(course_key, user, default_enrollment_mode.slug)
             mode = CourseMode.AUDIT if audit_mode else CourseMode.HONOR
             SAILTHRU_AUDIT_PURCHASE.send(
-                sender=None, event='enroll', user=user, mode=mode, course_id=course_key
+                sender=None, user=user, mode=mode, course_id=course_id
             )
             self._handle_marketing_opt_in(request, course_key, user)
             return DetailResponse(msg)
diff --git a/lms/djangoapps/email_marketing/signals.py b/lms/djangoapps/email_marketing/signals.py
index 3109f325d9f21c4337fa308786534ffb28362485..157cd6fc59e1d7bbbb01fe66a4ebb3fa9a9bddbe 100644
--- a/lms/djangoapps/email_marketing/signals.py
+++ b/lms/djangoapps/email_marketing/signals.py
@@ -41,7 +41,7 @@ SAILTHRU_AUDIT_PURCHASE_ENABLED = 'audit_purchase_enabled'
 
 
 @receiver(SAILTHRU_AUDIT_PURCHASE)
-def update_sailthru(sender, event, user, mode, course_id, **kwargs):
+def update_sailthru(sender, user, mode, course_id, **kwargs):  # pylint: disable=unused-argument
     """
     Receives signal and calls a celery task to update the
     enrollment track
@@ -52,9 +52,8 @@ def update_sailthru(sender, event, user, mode, course_id, **kwargs):
         None
     """
     if WAFFLE_SWITCHES.is_enabled(SAILTHRU_AUDIT_PURCHASE_ENABLED) and mode in CourseMode.AUDIT_MODES:
-        course_key = course_id
         email = str(user.email)
-        update_course_enrollment.delay(email, course_key, mode)
+        update_course_enrollment.delay(email, course_id, mode)
 
 
 @receiver(CREATE_LOGON_COOKIE)
diff --git a/lms/djangoapps/email_marketing/tests/test_signals.py b/lms/djangoapps/email_marketing/tests/test_signals.py
index d0b67cbf940a3a522de10659f7e14be7e31bfca7..2a96d0fd10b1bf6f9ae2dfa7c30de21a4c53d954 100644
--- a/lms/djangoapps/email_marketing/tests/test_signals.py
+++ b/lms/djangoapps/email_marketing/tests/test_signals.py
@@ -716,7 +716,7 @@ class SailthruTests(TestCase):
     @patch('sailthru.sailthru_client.SailthruClient.purchase')
     def test_switch_is_disabled(self, mock_sailthru_purchase):
         """Make sure sailthru purchase is not called when waffle switch is disabled"""
-        update_sailthru(None, None, self.user, 'verified', self.course_id)
+        update_sailthru(None, self.user, 'verified', self.course_id)
         self.assertFalse(mock_sailthru_purchase.called)
 
     @patch('openedx.core.djangoapps.waffle_utils.WaffleSwitchNamespace.is_enabled')
@@ -726,5 +726,5 @@ class SailthruTests(TestCase):
             i: waffle switch is True and mode is verified
         """
         switch.return_value = True
-        update_sailthru(None, None, self.user, 'verified', self.course_id)
+        update_sailthru(None, self.user, 'verified', self.course_id)
         self.assertFalse(mock_sailthru_purchase.called)