Please try invalidating caches (File | Invalidate caches, Invalidate and restart) – does the problem persist? Do you have @angular node_modules installed and included in project?
Also try reinstall npm packages:
npm install
My bookmarks and blogposts regarding Web Development in Angular, JavaScript, CSS, Html, C# and .NET
Please try invalidating caches (File | Invalidate caches, Invalidate and restart) – does the problem persist? Do you have @angular node_modules installed and included in project?
Also try reinstall npm packages:
npm install