TypeError: Cannot read property 'on' of undefined

[calvinti12]

After sending location I get this error

2018-10-01T01:16:02.484298+00:00 app[web.1]: /app/Bot/bloodBankBot.js:397
2018-10-01T01:16:02.484300+00:00 app[web.1]: user.eventEmitter.on('PhoneNumberMessageEvent', handlePhoneNumberMessageEvent);
2018-10-01T01:16:02.484302+00:00 app[web.1]: ^
2018-10-01T01:16:02.484303+00:00 app[web.1]:
2018-10-01T01:16:02.484304+00:00 app[web.1]: TypeError: Cannot read property 'on' of undefined