No provider for MatSnackBar

// error at task.component.ts
import { MatSnackBar } from '@angular/material/snack-bar';
function openSnackBar() {
this._snackBar.open('Your task has been successfully updated', 'Close', { duration: 2000 })
}
constructor(private _snackBar: MatSnackBar) {
})

Lisasin MatSnackBarModule task.moodule.tsja app.module.ts

// task.module.ts
import { NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
import { MatSnackBarModule } from '@angular/material/snack-bar';
@NgModule({
declarations: [
TaskComponent
],
imports: [
CommonModule,
MatSnackBarModule,
]
})

ja ka providers app.module.ts

// app.module.ts
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import { BrowserAnimationsModule } from '@angular/platform-browser/animations';
import { MatSnackBarModule } from '@angular/material/snack-bar';
@NgModule({
declarations: [
AppComponent,
],
imports: [
BrowserModule,
AppRoutingModule,
BrowserAnimationsModule,
MatSnackBarModule,
],
providers: [
MatSnackBarModule,
],
bootstrap: [AppComponent]
})