[BUG] Error random

[NEKERAFA]

A veces salta por el log

2019-05-19 17:35:49.448 14368-14368/com.gymkhanachain.app W/System.err: java.lang.NullPointerException: Attempt to read from field 'int android.support.v4.app.Fragment.mIndex' on a null object reference
2019-05-19 17:35:49.449 14368-14368/com.gymkhanachain.app W/System.err:     at android.support.v4.app.FragmentManagerImpl.saveFragmentInstanceState(FragmentManager.java:987)
2019-05-19 17:35:49.449 14368-14368/com.gymkhanachain.app W/System.err:     at com.gymkhanachain.app.ui.mainscreen.activities.MainActivity.onStop(MainActivity.java:278)
2019-05-19 17:35:49.449 14368-14368/com.gymkhanachain.app W/System.err:     at android.app.Instrumentation.callActivityOnStop(Instrumentation.java:1375)
2019-05-19 17:35:49.449 14368-14368/com.gymkhanachain.app W/System.err:     at android.app.Activity.performStop(Activity.java:7191)
2019-05-19 17:35:49.449 14368-14368/com.gymkhanachain.app W/System.err:     at android.app.ActivityThread.performStopActivityInner(ActivityThread.java:4032)
2019-05-19 17:35:49.449 14368-14368/com.gymkhanachain.app W/System.err:     at android.app.ActivityThread.handleStopActivity(ActivityThread.java:4084)
2019-05-19 17:35:49.449 14368-14368/com.gymkhanachain.app W/System.err:     at android.app.ActivityThread.-wrap24(Unknown Source:0)
2019-05-19 17:35:49.450 14368-14368/com.gymkhanachain.app W/System.err:     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1622)
2019-05-19 17:35:49.450 14368-14368/com.gymkhanachain.app W/System.err:     at android.os.Handler.dispatchMessage(Handler.java:106)
2019-05-19 17:35:49.450 14368-14368/com.gymkhanachain.app W/System.err:     at android.os.Looper.loop(Looper.java:164)
2019-05-19 17:35:49.450 14368-14368/com.gymkhanachain.app W/System.err:     at android.app.ActivityThread.main(ActivityThread.java:6494)
2019-05-19 17:35:49.450 14368-14368/com.gymkhanachain.app W/System.err:     at java.lang.reflect.Method.invoke(Native Method)
2019-05-19 17:35:49.452 14368-14368/com.gymkhanachain.app W/System.err:     at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
2019-05-19 17:35:49.452 14368-14368/com.gymkhanachain.app W/System.err:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)