diff --git a/src/helpers/stringHelper.ts b/src/helpers/stringHelper.ts
index b76a6aa..f41c660 100644
--- a/src/helpers/stringHelper.ts
+++ b/src/helpers/stringHelper.ts
@@ -9,6 +9,9 @@ export abstract class StringHelper {
     //   randomString += charSet.substring(randomPoz, randomPoz + 1);
     // }
     // return randomString;
-    return crypto.randomBytes(len).toString("base64");
+    return crypto
+      .randomBytes(len)
+      .toString("base64")
+      .replace(/[^a-zA-Z0-9]/g, "");
   }
 }