app-mascota' is not a known element

Hola he sigo paso a paso el curso pero grid-mascotas.component.html no me reconoce la etiqueta , ayuda por favor:

ERROR

src/app/mascotas/grid-mascotas/grid-mascotas.component.html:5:9 - error NG8001: 'app-mascota' is not a known element:
1. If 'app-mascota' is an Angular component, then verify that it is part of this module.
2. If 'app-mascota' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the '@NgModule.schemas' of this component to suppress this message.

5         <app-mascota
          ~~~~~~~~~~~~
6           [url]="mascota.url"
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7           [description]="mascota.description"
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8         ></app-mascota>
  ~~~~~~~~~

  src/app/mascotas/grid-mascotas/grid-mascotas.component.ts:6:16
    6   templateUrl: './grid-mascotas.component.html',
                     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    Error occurs in the template of component GridMascotasComponent.