Property in MobX is behaving weirdly

I am using Mobx in my react app.

Right now i have this property

    @observable
  messages: IObservableArray<MessageModel> = observable.array();

and then i have a method that uses that property

 @computed
  get AllMessages() {
    console.log('GETTING ALL MESSAGES', this.messages);
    const mostRecentReadMessage = this.getReadMessage();

   return {... some code}
}

The weird thing is, if log the content of this.messages i get the new messages values, but if i try to access it like this.messages[0].chat.text i get the old value.

Any help understanding this will be greatly appreciated.