diff --git a/icalendar_test.ts b/icalendar_test.ts
index 262455e..78941e5 100644
--- a/icalendar_test.ts
+++ b/icalendar_test.ts
@@ -182,7 +182,7 @@ Deno.test("expandRecurrences - object rrule (Reproduction of missing events)", (
   const icsEvent = {
     summary: "Object RRULE Event",
     start: startStr,
-    rrule: { freq: "WEEKLY", byday: "MO" } // Simulating object rrule
+    rrule: { frequency: "WEEKLY", byday: "MO" } // Simulating object rrule with verbose key
   };
   
   // Spy on console.warn