Why MAT_DATE_LOCALE does not apply language?

I use this code to set language for MAT_DATEPICKER element:

import { MAT_DATE_LOCALE } from "@angular/material";

@Component({
selector: "oputax-report",
providers: [{ provide: MAT_DATE_LOCALE, useValue: "fr-FR" }]
})


But there is not effect, it is still in English

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