...

app/src/main/java/com/example/pap_teste/GestaoStaffActivity.java

@@ -225,7 +225,7 @@ public class GestaoStaffActivity extends AppCompatActivity {
 
                 for (DataSnapshot postSnapshot : snapshot.getChildren()) {
                     Staff staff = postSnapshot.getValue(Staff.class);
-                    if (staff != null) {
+                    if (staff != null && staff.getName() != null) {
                         staffList.add(staff);
                         staffNames.add(staff.getName());