diff --git a/automated-orders/packages/blockchain-library/src/clients/warden.ts b/automated-orders/packages/blockchain-library/src/clients/warden.ts
index 591a6d045..6ff09debc 100644
--- a/automated-orders/packages/blockchain-library/src/clients/warden.ts
+++ b/automated-orders/packages/blockchain-library/src/clients/warden.ts
@@ -21,7 +21,7 @@ export class WardenClient {
   }
 
   async *pollSignatureRequests(): AsyncGenerator<INewSignatureRequest> {
-    let nextKey: Uint8Array | undefined = new Uint8Array();
+    let nextKey: Uint8Array | undefined = undefined;
 
     while (true) {
       await delay(this.configuration.pollingIntervalMsec);
diff --git a/automated-orders/packages/utils-library/src/services/cache.ts b/automated-orders/packages/utils-library/src/services/cache.ts
index 1897c6c5d..a96adfe24 100644
--- a/automated-orders/packages/utils-library/src/services/cache.ts
+++ b/automated-orders/packages/utils-library/src/services/cache.ts
@@ -41,7 +41,10 @@ export class LruCache<T> {
     }
     
     private refresh(key: string) {
-        const entry = this.values.get(key)!;
+        const entry = this.values.get(key);
+        if (entry === undefined) {
+            throw new Error(`Key ${key} not found in cache`);
+        }
         this.values.delete(key);
         this.values.set(key, entry);
         return entry;