Flashdata clearing after redirect

Hello, 
Flashdata is clearing up after I do the redirect.
My code:

PHP Code:

    public function deleteGroup()
    {

        $model = new \App\Models\GroupModel();

        $post = $this->request->getPost();
        if ($post) {
            session()->setFlashdata('success', 'Grupo removido com sucesso');
        }
        return redirect()->to('groups');
    } 


But if I remove the redirect and return a view, it works correctly:

PHP Code:

public function deleteGroup()
    {

        $model = new \App\Models\GroupModel();

        $post = $this->request->getPost();
        if ($post) {
            session()->setFlashdata('success', 'Grupo removido com sucesso');
        }
        return view('group');
    } 


What am I doing wrong?