V-model ion-datetime with ion-datetime-button

I have a problem, I can not figure out how to bind v-model to ion-datetime.
This only works for the first time change, after that the data does not change dynamically

<template>
  <ion-datetime-button datetime="datetime"></ion-datetime-button>
  
  <ion-modal :keep-contents-mounted="true">
    <ion-datetime id="datetime" v-model="selected"></ion-datetime>
  </ion-modal>
</template>