Undefined token issue when refreshing a new bearer token

I have an application that goes through the login page with username and password credentials and then has a get request with /dev/users/current which has the bearer token I would like to refresh when it’s old. I am getting a 401 error on the current page, a 200 status on the login page and this error (New token has been set: undefined).

I also set environmental variables for authSericeUrl and gatewayUrl as well as the credentials

Does anyone know the problem

var authServiceUrl = pm.environment.get('authServiceUrl');

var gatewayBaseUrl = pm.environment.get('gatewayUrl');

var username = pm.environment.get('username');

var password = pm.environment.get('password');

var sdk = require('postman-collection');

var isValidTokenRequest = new sdk.Request({

    url: gatewayBaseUrl + "/dev/users/current", // Use an endpoint that requires being authenticated

    method: 'GET',

    header: [

        new sdk.Header({

            key: 'content-type',

            value: 'application/json',

        }),

        new sdk.Header({

            key: 'acccept',

            value: 'application/json',

        }),

        new sdk.Header({

            key: 'Authorization',

            value: 'Bearer ' + pm.environment.get("jwtToken"),

        }),

    ]

});

pm.sendRequest(isValidTokenRequest, function (err, response) {

    if (response.code === 401) {

        refreshToken();

    }

});

function refreshToken() {

    var tokenRequest = new sdk.Request({

    url: authServiceUrl,

    method: 'POST',

    header: [

        new sdk.Header({

            key: 'content-type',

            value: 'application/json'

        }),

        new sdk.Header({

            key: 'acccept',

            value: 'application/json'

        }),

    ],

    body: {

        mode: 'raw',

        raw: JSON.stringify({

            username: username,

            password: password

        })

    } 

  });

  pm.sendRequest(tokenRequest, function (err, response) {

      if (err) {

          throw err;

      }

      

      if (response.code !== 200) {

          throw new Error('Could not log in.');

      }

      

      pm.environment.set("jwtToken", response.json().token);

      console.log(`New token has been set: ${response.json().token}`);

  });

}