IonMenu breaks navigation because IonPage is missing - it's not

Hi, I’ve a HomePage that has menu and content. I followed the Menu documentation, so it looks like this:

<template>
  <ion-menu content-id="main-content">
    <ion-header>
      <ion-toolbar>
        <ion-title>APP</ion-title>
      </ion-toolbar>
    </ion-header>
    <ion-content class="ion-padding">
      <ion-list id="inbox-list">
        <ion-note class="ion-padding ion-margin-top">
          {{ user?.["default_name"] }}
        </ion-note>

        <ion-item @click="logout">
          <ion-label>Odhlásiť sa</ion-label>
        </ion-item>
      </ion-list>
    </ion-content>
  </ion-menu>
  <ion-page id="main-content">
    <ion-header>
      <ion-toolbar>
        <ion-buttons slot="start">
          <ion-menu-button :autoHide="false"></ion-menu-button>
        </ion-buttons>
        <ion-title>Domov</ion-title>
      </ion-toolbar>
    </ion-header>
    <ion-content :fullscreen="true">
      <ion-list>
        <ion-item
          class="ion-margin-vertical"
          router-link="/projects/photos/create"
        >
          <ion-label><h1>Odfotiť zákazku</h1></ion-label>
        </ion-item>
      </ion-list>
    </ion-content>
  </ion-page>
</template>

However, when I navigate to page like photos/create and then try to go back, I get these errors:

image

When I comment out the Menu part like this, everything works:

<template>
  <ion-page id="main-content">
    <ion-header>
      <ion-toolbar>
        <ion-buttons slot="start">
          <ion-menu-button :autoHide="false"></ion-menu-button>
        </ion-buttons>
        <ion-title>Domov</ion-title>
      </ion-toolbar>
    </ion-header>
    <ion-content :fullscreen="true">
      <ion-list>
        <ion-item
          class="ion-margin-vertical"
          router-link="/projects/photos/create"
        >
          <ion-label><h1>Odfotiť zákazku</h1></ion-label>
        </ion-item>
      </ion-list>
    </ion-content>
  </ion-page>
</template>

Well, except the menu, because it’s not there. Why does this happen and how can I fix it?
Thank you very much.

i would suggest that you start your project using one of the provided ionic templates so that you can get a basic understanding of how the components and navigation work.