'mat-label' is not a known element Error in latest Angular Material

I got an error in my Angular Material:

compiler.js:466 Uncaught Error: Template parse errors:
'mat-label' is not a known element:
1. If 'mat-label' is an Angular component, then verify that it is part of this module.
2. If 'mat-label' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the '@NgModule.schemas' of this component to suppress this message. ("
        </mat-form-field>
        <mat-form-field>
            [ERROR ->]<mat-label>Both a label and a placeholder</mat-label>
            <input matInput placeholder="Simple"): 

Question:

Material Label is under MatFormFieldModule Here's the link

Now, what is the possible cause of the issue why Mat-Label is unknown to Angular Material.

Here is the HTML

> > Both a label and a placeholder > >

If you have multiple modules make sure you're importing the MatFormFieldModule in every module. It's not sufficient to just import it in the root module.

For example, I have a CommonWidgetsModule which contains some common widgets (my own) and you'll see I'm importing MatFormFieldModule and MatInputModule

// common-widgets.module.ts
import { MatFormFieldModule } from '@angular/material/form-field';
import { MatInputModule } from '@angular/material/input';

@NgModule({
  imports: [
    CommonModule,
    SharedModule,
    RouterModule,

    MatFormFieldModule,
    MatInputModule,

    // import other MatModules...

  ],
  declarations: DECLARATIONS,
  exports: DECLARATIONS
})
export class CommonWidgetsModule { }

Could also be that you forgot to add your component in your module (that is already importing MatFormFieldModule and MatInputModule.

Make sure that you are importing MatFormFieldModule in 'app.module.ts' or respective module's 'module.ts' file.

@NgModule({ 
  imports: [
    BrowserModule, 
    FormsModule, 
    MatFormFieldModule,
  ],
})

in app.module.ts file add

import {FormsModule} from "@angular/forms";

imports:[
FormsModule
]

FormModule Includes all the Fields Related to Form

I also found if you use the CLI and say skip-import. This will then result in the component not appear in your module. So it will not reference back to the imports for the mat label.

Upgrade @angular/material to "5.2.0" and the problem will go away.