Полный код: https://github.com/Khuzha/bots/blob/master/comment/index.js

Reply

*Мне нужно узнать, на чье сообщение отвечает юзер

Пишу 
console.log(ctx.update.message.reply_to_message.from.id)

для:

{"update_id":271606609,"message":{"message_id":294,"from":{"id":62253745,"is_bot":false,"first_name":"Endorphine","username":"Khuzha","language_code":"ru"},"chat":{"id":62253745,"first_name":"Endorphine","username":"Khuzha","type":"private"},"date":1536767250,"reply_to_message":{"message_id":283,"from":{"id":667423748,"is_bot":true,"first_name":"Khuzha","username":"KhuzhaBot"},"chat":{"id":62253745,"first_name":"Endorphine","username":"Khuzha","type":"private"},"date":1536766748,"forward_from":{"id":346724642,"is_bot":false,"first_name":"Jakhongir","username":"itashpik","language_code":"en-US"},"forward_date":1536766748,"text":"Не работает"},"text":";\\"}}

Выходит ошибка:

  TypeError: Cannot read property 'from' of undefined
      at bot.on (/home/oneuser/MyProjects/bots/contactbot/index.js:23:51)
      at Promise.resolve.then (/home/oneuser/MyProjects/bots/contactbot/node_modules/telegraf/composer.js:107:56)
      at <anonymous>
      at process._tickCallback (internal/process/next_tick.js:188:7)

Failed to process updates. TypeError: Cannot read property 'from' of undefined
    at bot.on (/home/oneuser/MyProjects/bots/contactbot/index.js:23:51)
    at Promise.resolve.then (/home/oneuser/MyProjects/bots/contactbot/node_modules/telegraf/composer.js:107:56)
    at <anonymous>
    at process._tickCallback (internal/process/next_tick.js:188:7)