diff --git a/src/main/kotlin/g2601_2700/s2622_cache_with_time_limit/solution.ts b/src/main/kotlin/g2601_2700/s2622_cache_with_time_limit/solution.ts
index cbe76b904..f23053e51 100644
--- a/src/main/kotlin/g2601_2700/s2622_cache_with_time_limit/solution.ts
+++ b/src/main/kotlin/g2601_2700/s2622_cache_with_time_limit/solution.ts
@@ -1,7 +1,7 @@
 // #Medium #2023_08_31_Time_51_ms_(94.82%)_Space_42.2_MB_(94.26%)
 
 class TimeLimitedCache {
-    private keyMap: Map<number, any>
+    private readonly keyMap: Map<number, any>
     constructor() {
         this.keyMap = new Map<number, any>()
     }