diff --git a/src/code42cli/cmds/cases.py b/src/code42cli/cmds/cases.py
index dc862967..be415d5a 100644
--- a/src/code42cli/cmds/cases.py
+++ b/src/code42cli/cmds/cases.py
@@ -275,7 +275,7 @@ def bulk(state):
 
 FILE_EVENTS_HEADERS = [
     "number",
-    "eventId",
+    "event_id",
 ]
 
 case_file_events_generate_template = generate_template_cmd_factory(
@@ -288,15 +288,15 @@ def bulk(state):
 @bulk.command(
     name="add",
     help="Bulk associate file events to cases using a CSV file with "
-    "format: {}.".format(",".join(FILE_EVENTS_HEADERS)),
+    f"format: {','.join(FILE_EVENTS_HEADERS)}.",
 )
 @read_csv_arg(headers=FILE_EVENTS_HEADERS)
 @sdk_options()
 def bulk_add(state, csv_rows):
     sdk = state.sdk
 
-    def handle_row(case_number, event_id):
-        sdk.cases.file_events.add(case_number, event_id)
+    def handle_row(number, event_id):
+        sdk.cases.file_events.add(number, event_id)
 
     run_bulk_process(
         handle_row, csv_rows, progress_label="Associating file events to cases:",
@@ -306,15 +306,15 @@ def handle_row(case_number, event_id):
 @bulk.command(
     name="remove",
     help="Bulk remove the file event association from cases using a CSV file with "
-    "format: {}.".format(",".join(FILE_EVENTS_HEADERS)),
+    f"format: {','.join(FILE_EVENTS_HEADERS)}.",
 )
 @read_csv_arg(headers=FILE_EVENTS_HEADERS)
 @sdk_options()
 def bulk_remove(state, csv_rows):
     sdk = state.sdk
 
-    def handle_row(case_number, event_id):
-        sdk.cases.file_events.delete(case_number, event_id)
+    def handle_row(number, event_id):
+        sdk.cases.file_events.delete(number, event_id)
 
     run_bulk_process(
         handle_row,
diff --git a/tests/cmds/test_cases.py b/tests/cmds/test_cases.py
index 25392b3f..ee646ac8 100644
--- a/tests/cmds/test_cases.py
+++ b/tests/cmds/test_cases.py
@@ -472,15 +472,15 @@ def test_add_bulk_file_events_to_cases_uses_expected_arguments(
     bulk_processor = mocker.patch("code42cli.cmds.cases.run_bulk_process")
     with runner.isolated_filesystem():
         with open("test_add.csv", "w") as csv:
-            csv.writelines(["number,eventId\n", "1,abc\n", "2,pqr\n"])
+            csv.writelines(["number,event_id\n", "1,abc\n", "2,pqr\n"])
         runner.invoke(
             cli,
             ["cases", "file-events", "bulk", "add", "test_add.csv"],
             obj=cli_state_with_user,
         )
     assert bulk_processor.call_args[0][1] == [
-        {"number": "1", "eventId": "abc"},
-        {"number": "2", "eventId": "pqr"},
+        {"number": "1", "event_id": "abc"},
+        {"number": "2", "event_id": "pqr"},
     ]
 
 
@@ -490,13 +490,13 @@ def test_remove_bulk_file_events_from_cases_uses_expected_arguments(
     bulk_processor = mocker.patch("code42cli.cmds.cases.run_bulk_process")
     with runner.isolated_filesystem():
         with open("test_remove.csv", "w") as csv:
-            csv.writelines(["number,eventId\n", "1,abc\n", "2,pqr\n"])
+            csv.writelines(["number,event_id\n", "1,abc\n", "2,pqr\n"])
         runner.invoke(
             cli,
             ["cases", "file-events", "bulk", "remove", "test_remove.csv"],
             obj=cli_state_with_user,
         )
     assert bulk_processor.call_args[0][1] == [
-        {"number": "1", "eventId": "abc"},
-        {"number": "2", "eventId": "pqr"},
+        {"number": "1", "event_id": "abc"},
+        {"number": "2", "event_id": "pqr"},
     ]