diff --git a/utils/TimerMgr.js b/utils/TimerMgr.js
index 3194248..a63abe2 100644
--- a/utils/TimerMgr.js
+++ b/utils/TimerMgr.js
@@ -66,6 +66,10 @@ class TimerMgr {
     }
 
     reschedule(id, timeout) {
+        if (!this.hasTimer(id)) {
+            log.warn(`Cannot reschedule non-existent timer with id ${id}`);
+            return false;
+        }
         this.#timers[id].reschedule(timeout);
     }
 }