Multiple components match node with tagname app-lobby

Question

the code was running fine on angular version 8.3.4 but when i updated it to the latest version of angular ( 9 ) i got the following error

following is t

Answer 1

I have an app in angular 9. I had similar problem, but then i realised that i forgot the provider for DatePipe. After that, this error went away... Maybe errors like these won't be happening after some time of angular 9 development.