How to fix : AADSTS500126: External ID token from issuer '{issuer}' failed signature verification. KeyID of token is '{keyid}'.

I am working on creating external authentication method using OpenID connect flow.

Now I am looking for the last step where the generated id_token from issuer need to verify by Microsoft Entra ID. However, I am getting the following error :

AADSTS500126: External ID token from issuer 'https://xxxx' failed signature verification. KeyID of token is 'xxxxxxx'.

Generating id_token using following params, what could be the issue, I tried verifying the id_token generated on https://jwt.io/ and https://jwt.davetonge.co.uk/ it shows signature verified.

Looking for help here to resolved the issue. Thank you.

$payload = [
            'iss' => "xxxx",
            'tid' => "xxxx",
            'aud' => "xxxx",
            'exp' => time() + 3600,
            'iat' => time(),
            'nbf' => time(),
            'sub' => $entra_data['sub'],
            'nonce' => $entra_data['nonce'],
            'acr' => $entra_data['acr'],
            'amr' => $entra_data['amr'],
            'name' => $user->name,
            'email' => $user->email,
            'preferred_username' => $user->email
        ];

        // Create the header
        $header = [
            'alg' => 'RS256',
            'typ' => 'JWT',
            'kid' => "xxxxxx"
        ];
        
        return $id_token = JWT::encode($payload, $privateKey, 'RS256', null, $header);