diff --git a/src/core/main/custom/hotkey.ts b/src/core/main/custom/hotkey.ts
index 9df772c..044a5cd 100644
--- a/src/core/main/custom/hotkey.ts
+++ b/src/core/main/custom/hotkey.ts
@@ -200,7 +200,7 @@ export class Hotkey extends EventEmitter<HotkeyEvent> {
     set(id: string, key: KeyCode, assist: number, emit: boolean = true) {
         const { ctrl, shift, alt } = unwarpBinary(assist);
         const data = this.data[id];
-        const before = this.keyMap.get(data.key)!;
+        const before = this.keyMap.get(data?.key ?? KeyCode.Unknown)!;
         deleteWith(before, data);
         this.ensureMap(key);
         const after = this.keyMap.get(key)!;