MomentJS + VueJS: Getting Relative Time From Now To A Certain Point In The Past

I use MomentJS.

in my VueJS-Code I want to get the relative time from now to that point in the past. In my template I incorporate the result of this short piece of JavaScript:

<template>
  <div>{{ moment(message.createdAt, 'YYYYMMDD').fromNow() }}</div>
</template>

the object receives the date as follows:

message: { createdAt: Date.now() }

the result is always: a few seconds ago ...

how can I get the correct result (not always "a few seconds ago"):

EDIT:

this is my full template:

<template v-for="message in messages">
  <div class="message">
    <div class="text">{{ message.text }}</div>
    <div class="date">{{ moment(message.createdAt).format('D.M.YYYY') }}</div>
    <div class="date">{{ moment(message.createdAt).fromNow() }}</div>
  </div>
</template>