How can I close a JitsiMeet room using code?

Question

I'm doing some tests to close the JitsiMeet call via code, I tried a few things but it gave an error.

tried

jitsiMeetActivity.finish();

I also tried

jitsiMeetActivity.leave();

In both cases the error

java.lang.NullPointerException: Attempt to invoke virtual method 'void org.jitsi.meet.sdk.JitsiMeetActivity.finish()' on a null object reference

My code

try {
     JitsiMeetConferenceOptions defaultOptions = new JitsiMeetConferenceOptions.Builder().
     setServerURL(new URL("https://meet.jit.si"))
    .setFeatureFlag("chat.enabled",false)
    .setFeatureFlag("invite.enabled",false)
    .setWelcomePageEnabled(false).build();
    JitsiMeet.setDefaultConferenceOptions(defaultOptions);

    Date data = new Date(System.currentTimeMillis());
    SimpleDateFormat formatDate = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
    salas.setSala(nomeSala);
    salas.setEmailCreator(email);
    salas.setDate(formatDate.format(data));
    salas.setEmailParticipant("");
    salas.setRoomAtive(true);
                                    
    db.collection("Salas").document(nomeSala).set(salas).addOnSuccessListener(new OnSuccessListener<Void>() {
     @Override
     public void onSuccess(Void unused) {
          Toast.makeText(getContext(), "Room Created", Toast.LENGTH_SHORT);

          JitsiMeetConferenceOptions options = new JitsiMeetConferenceOptions.Builder().setRoom(salas.getSala()).setWelcomePageEnabled(false).build();
         jitsiMeetActivity.launch(getContext(), options);
         try{
              jitsiMeetActivity.finish();
         }catch (Exception e){
              Log.d("Error",e.toString());
      }    

   }

 });
    
 }catch (MalformedURLException e){
       e.printStackTrace();
 }

The intention is for the code to go back to the fragment that calls JitsiMeet.