Reload a Fragment

everyone, my issue is :

I'm in ProfilFragment, that was generated with the Menu Drawer it extends Fragment, and I can't change this (it broke some other part). When I click on a button I want to refresh my current Fragment

// Reload current fragment
                        Fragment frg = null;
                        frg = getActivity().getSupportFragmentManager().findFragmentById(R.id.nav_profil);
                        FragmentTransaction ft = getActivity().getSupportFragmentManager().beginTransaction();
                        ft.detach(frg);
                        ft.attach(frg);
                        ft.commit();

I found this on other StackOverflow issues but it didn't work for me. frg = getActivity().getSupportFragmentManager().findFragmentById(R.id.nav_profil); Always return null

Even if in my mobile_navigation.xml I have

<fragment
    android:id="@+id/nav_profil"
    android:name="com.example.pierregignoux.ui.profil.ProfilFragment"
    tools:layout="@layout/fragment_profil" />

Any help would be great, Thanks a lot.

Copyright Notice：Content Author:「Beatles BOB」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/60433365/reload-a-fragment