Method AppHttpControllersCD4Controller::importcd4 does not exist. Facing this error

I want to upload excel file to database table CD4 and i am facing issue this method cant find

Route::get('importcd4',[CD4Controller::class, 'importcd4'])->name('importcd4');

here is controller function

  public function  importcd4(){
        Excel::import(new CD4, request()->file('file')->store('files'));
    return redirect()->route('cd4.index')->with('success');
    }
}

Need Solution for that and i why its showing this error to me….