# \[Archive\] Error: Unexpected token ‘I’, “Invalid en”… is not valid JSON

**URL:** <https://builder.metamask.io/t/archive-error-unexpected-token-i-invalid-en-is-not-valid-json/1769>\
**Category:** Embedded Wallets (Web3Auth)\
**Created:** [October 2, 2023, 10:39am UTC](https://builder.metamask.io/t/archive-error-unexpected-token-i-invalid-en-is-not-valid-json/1769 "2023-10-02T10:39:49Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![KFMroot](https://avatars.discourse-cdn.com/v4/letter/k/3be4f8/32.png) [@KFMroot](https://builder.metamask.io/u/KFMroot)\
**Post date:** [October 2, 2023, 10:39am UTC](https://builder.metamask.io/t/archive-error-unexpected-token-i-invalid-en-is-not-valid-json/1769/1 "2023-10-02T10:39:49Z")

</div>

> **🏛 Archived Content from Web3Auth Community**
> 
> This topic was originally posted by **KFMroot** on 10/2/2023.  
> This content has been migrated from our previous community forum to preserve valuable discussions.

* * *

Hello, since I updated my openlogin-adapter from v4 to v5, I’ve been getting this error message with my custom JWT connection: “Unexpected token ‘I’, “Invalid en”… is not valid JSON”.

- SDK Version: 7.0.1
- Platform: Chrome Version 117.0.5938.92 (Build officiel) (64 bits)
- Browser Console Screenshots:

[![Capture](https://canada1.discourse-cdn.com/flex011/uploads/metamaskbuilderhub/original/2X/2/2a4a8427cd4052b1d398b47e244e267bae1c23ee.png)
Capture1079×662 47.7 KB
](https://web3auth.io/community/uploads/default/original/2X/d/d38bbc3a13f5c8a7211f89be1df2e56218004282.png "Capture")

- JWT token : {  
“sub”: “d6f3adef-27fb-4ad6-80fd-b4d0f7811471”,  
“id”: 96,  
“username”: “KFMroot”,  
“email”: “[e@mail.com](mailto:e@mail.com)”,  
“role”: “ADMIN”,  
“email\_verified”: true,  
“aud”: “[https://website.com](https://website.com/)”,  
“iss”: “[https://website.com](https://website.com/)”,  
“iat”: 1696240273,  
“exp”: 1696243873  
}

```auto
import { Web3AuthNoModal } from "@web3auth/no-modal";
import { CHAIN_NAMESPACES } from '@web3auth/base';
import { OpenloginAdapter } from '@web3auth/openlogin-adapter';
import { CLIENT_ID } from 'config';
import { EthereumPrivateKeyProvider } from "@web3auth/ethereum-provider";
const chainConfig = {
chainNamespace: CHAIN_NAMESPACES.EIP155,
chainId: ‘0x13881’,
displayName: “Polygon Mumbai Testnet”,
blockExplorer: “https://mumbai.polygonscan.com/”,
ticker: “MATIC”,
tickerName: “Matic”,
rpcTarget: ‘https://polygon-mumbai.g.alchemy.com/v2/{key}’
}
export const Web3auth = new Web3AuthNoModal({
clientId: CLIENT_ID,
chainConfig,
web3AuthNetwork: “legacy_mainnet”,
useCoreKitKey: false,
});
const isMobile = /iPhone|iPad|iPod|Android/i.test(window.navigator.userAgent);
const privateKeyProvider = new EthereumPrivateKeyProvider({ config: { chainConfig } });
export const openloginAdapter = new OpenloginAdapter({
chainConfig,
adapterSettings: {
clientId: CLIENT_ID,
web3AuthNetwork: “legacy_mainnet”,
uxMode: isMobile ? “redirect” : “popup”, // Conditionally set uxMode based on mobile detection
loginConfig: {
jwt: {
verifier: ‘verifier_name’,
typeOfLogin: ‘jwt’,
clientId: CLIENT_ID,
},
},
},
privateKeyProvider,
});

```

---

<div class="post-metadata">

**Author:** ![yohan.chiovetta](https://avatars.discourse-cdn.com/v4/letter/y/d78d45/32.png) [@yohan.chiovetta](https://builder.metamask.io/u/yohan.chiovetta)\
**Post date:** [October 2, 2023, 1:14pm UTC](https://builder.metamask.io/t/archive-error-unexpected-token-i-invalid-en-is-not-valid-json/1769/2 "2023-10-02T13:14:13Z")

</div>

@maharshi @vjgee can you help us ?

---

<div class="post-metadata">

**Author:** ![maharshi](https://yyz1.discourse-cdn.com/flex011/user_avatar/builder.metamask.io/maharshi/32/1525_2.png) [@maharshi](https://builder.metamask.io/u/maharshi)\
**Post date:** [October 2, 2023, 1:27pm UTC](https://builder.metamask.io/t/archive-error-unexpected-token-i-invalid-en-is-not-valid-json/1769/3 "2023-10-02T13:27:14Z")

</div>

Hey @KFMroot @yohan.chiovetta can you give me the name of the verifier that you’re using?

---

<div class="post-metadata">

**Author:** ![KFMroot](https://avatars.discourse-cdn.com/v4/letter/k/3be4f8/32.png) [@KFMroot](https://builder.metamask.io/u/KFMroot)\
**Post date:** [October 2, 2023, 1:31pm UTC](https://builder.metamask.io/t/archive-error-unexpected-token-i-invalid-en-is-not-valid-json/1769/4 "2023-10-02T13:31:36Z")

</div>

```
   hey! it's zwapx-custom-jwt

```