Cannot read property 'id' of undefined

[geraldoramos]

I'm getting these errors when trying to use postMessageToUser. Some users works fine, some crashes with this error.

error: {
message: Cannot read property 'id' of undefined, 
name: TypeError, 
stack: 
TypeError: Cannot read property 'id' of undefined
    at Bot.<anonymous> (/opt/slack-integration-api-internal/node_modules/slackbots/index.js:246:56)
    at Array.<anonymous> (/opt/slack-integration-api-internal/node_modules/vow/lib/vow.js:773:56)
    at Immediate.callFns (/opt/slack-integration-api-internal/node_modules/vow/lib/vow.js:24:35)
    at processImmediate (timers.js:632:19)
    at process.topLevelDomainCallback (domain.js:120:23)
}

This is where the error is happening: (slackbots index.js):

getChatId(name) {
        return this.getUser(name).then(function(data) {

            var chatId = _.find(this.ims, { user: data.id }); // here is the problem

            return (chatId && chatId.id) || this.openIm(data.id);
        }.bind(this)).then(function(data) {
            return typeof data === 'string' ? data : data.channel.id;
        });
    }

This is my postMessageToUser wrapper:

const SlackBot = require('slackbots')

module.exports = {
  postMessageToUser: async(name, info, message, token) => {
    return new Promise((resolve) => {
      const bot = new SlackBot({
        token,
        disconnect: true,
      })
      bot.postMessageToUser(name, info, message, data => {
        resolve(data)
      })
    });
  },

}

Any thoughts? I'm sure the user being received by the postMessageToUser function is a valid user in the given workspace.

Thanks in advance,

Geraldo