Clicking any file or folder on OTG after the device has been removed caused Amaze file manager v 3.2.1 to crash

Project Information

Repository: https://github.com/TeamAmaze/AmazeFileManager
Project Name: Amaze File Manager

Expected Behavior

I expected that after I ejected my OTG flash drive, the location wouldn't be available on the file manager and even it's still available, clicking on it will have no effect.

Actual Behavior

The OTG directory doesn't close when the OTG flash drive was ejected, it looked like though the OTG flash drive was still connected because all the contents were still visible after the drive was removed and clicking any file or folder caused the app to crash.

Steps to Reproduce

plug in OTG flash drive
launch amaze file manager
swipe from left to right to reveal menus, shortcuts and options
select OTG and allow access
after OTG storage is open on the file manager, eject the drive either forcefully or using the eject button on notifications panel
the contents of the OTG flash drive is still open even after ejection and clicking any content on it will causes the app to crash.

Test Environment

Device: Tecno Camon CM
OS Version: Android 7.0
Software Version: v3.2.1

Logcat

FATAL EXCEPTION: main
Process: com.amaze.filemanager, PID: 29998
java.lang.NullPointerException: Attempt to invoke virtual method 'android.support.v4.provider.DocumentFile android.support.v4.provider.DocumentFile.findFile(java.lang.String)' on a null object reference
    at com.amaze.filemanager.utils.OTGUtil.getDocumentFile(OTGUtil.java:95)
    at com.amaze.filemanager.fragments.MainFragment.onListItemClicked(MainFragment.java:922)
    at com.amaze.filemanager.adapters.RecyclerAdapter$1.onClick(RecyclerAdapter.java:401)
    at android.view.View.performClick(View.java:6076)
    at android.view.View$PerformClick.run(View.java:23138)
    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:6292)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1094)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:955)

Recording of the bug

Proof of Work Done

This is the link to my github account