diff --git a/lib/index.js b/lib/index.js
index 72ffbb7..38f3b08 100755
--- a/lib/index.js
+++ b/lib/index.js
@@ -149,8 +149,10 @@ internals.Yar = class {
         if (this._store._lazyKeys) {
             this._isLazy = true;                         // Default to lazy mode if previously set
             for (const key of this._store._lazyKeys) {
-                this[key] = this._store[key];
-                delete this._store[key];
+                if (key in this._store) {
+                    this[key] = this._store[key];
+                    delete this._store[key];
+                }
             }
         }
     }