App crashes on elifut

Project Information
Repository: https://github.com/EliFUT/android
project name: Elifut
publisher: felipe lima

Expected behavior :

1. When i open home activity which contains two tabs; players and info item, then i switch my device to landscape; and tap on the players tab, it should should show me the details of the players tab i clicked.

Actual behavior:

1.When i open home activity which contains two tabs; players and info item, then i switch to landscape;and tap on the players tab, instead of showing the details of the tab i clicked, it crashes.

How to reproduce

1. Open Elifut
2. Choose a country if you have not already chosen one before
3. Wait for it to download game data
4. Once the page loads,switch to landscape
5. Click the players tab
6. App crashes

App version: 1.0.6

Device 1
Operating system: Android Nougat- 7.0
model: Infinix Hot 4
Device 2
Operating system: Android Nougat- 7.0
model: infinix s2 pro

Recording of the bug:
device 1:

device2:

###logcat

                                                   Process: com.elifut, PID: 23181
                                                   java.lang.IllegalArgumentException: Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkParameterIsNotNull, parameter $receiver
                                                       at com.elifut.models.PlayersKt.goalkeepers(Players.kt)
                                                       at com.elifut.fragment.TeamSquadFragment.onPlayersLoaded(TeamSquadFragment.java:112)
                                                       at com.elifut.fragment.TeamSquadFragment.setUserVisibleHint(TeamSquadFragment.java:105)
                                                       at android.support.v4.app.FragmentPagerAdapter.setPrimaryItem(FragmentPagerAdapter.java:136)
                                                       at android.support.v4.view.ViewPager.populate(ViewPager.java:1234)
                                                       at android.support.v4.view.ViewPager.setCurrentItemInternal(ViewPager.java:662)
                                                       at android.support.v4.view.ViewPager.setCurrentItemInternal(ViewPager.java:624)
                                                       at android.support.v4.view.ViewPager.setCurrentItem(ViewPager.java:605)
                                                       at android.support.design.widget.TabLayout$ViewPagerOnTabSelectedListener.onTabSelected(TabLayout.java:2170)
                                                       at android.support.design.widget.TabLayout.dispatchTabSelected(TabLayout.java:1165)
                                                       at android.support.design.widget.TabLayout.selectTab(TabLayout.java:1158)
                                                       at android.support.design.widget.TabLayout.selectTab(TabLayout.java:1128)
                                                       at android.support.design.widget.TabLayout$Tab.select(TabLayout.java:1427)
                                                       at android.support.design.widget.TabLayout$TabView.performClick(TabLayout.java:1537)
                                                       at android.view.View$PerformClick.run(View.java:23235)
                                                       at android.os.Handler.handleCallback(Handler.java:836)
                                                       at android.os.Handler.dispatchMessage(Handler.java:103)
                                                       at android.os.Looper.loop(Looper.java:203)
                                                       at android.app.ActivityThread.main(ActivityThread.java:6251)
                                                       at java.lang.reflect.Method.invoke(Native Method)
                                                       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1073)
                                                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:934)

Github Account
https://github.com/a-ndi