Application Crashing

[pcsaunak]

As soon as I try to submit any thing it crashes, for example, when the app first starts up, it asks for password. When I type the password for the second time it crashes. with the below error

android.view.WindowManager$BadTokenException: Unable to add window -- token null is not valid; is your activity running?

the same thing happens if I try to open the app again ,it navigates from splash screen to the home screen where I need to add my expense. As soon as I enter the number and hit the "Ok" button on the soft keyboard the app crashes . Here is the complete crash log.
Tried running the app on android 8 and android 7 but the same.
I did update the app a bit so that I could compile it in the latest android studio version.
Also updated the "@Linkview" of butterknife to "@BindView"

05-30 02:38:04.303 29347-29347/com.nightonke.cocoin E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.nightonke.cocoin, PID: 29347
android.view.WindowManager$BadTokenException: Unable to add window -- token null is not valid; is your activity running?
at android.view.ViewRootImpl.setView(ViewRootImpl.java:679)
at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:342)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:93)
at com.github.johnpersano.supertoasts.ManagerSuperToast.displaySuperToast(ManagerSuperToast.java:189)
at com.github.johnpersano.supertoasts.ManagerSuperToast.handleMessage(ManagerSuperToast.java:146)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
at android.app.ActivityThread.main(ActivityThread.java:6119)
at java.lang.reflect.Method.invoke(Native Method)