I have some issues with importing components/services in stackblitz. Please look at the files sidebar.component.ts, layout.component.ts and layout.module.ts. I tried many forms, no success.
Here is the stackblitz link: https://stackblitz.com/edit/angular-ivy-pksnff?file=src/app/components/layout/layout.module.ts
EDIT: it turnet out, that all was fine, I had to restart the stackblitz ide.