crash on click "send file" button

Look like connected:

08-21 11:07:07.911 22644 22644 D AndroidRuntime: Shutting down VM
08-21 11:07:07.920 22644 22644 E AndroidRuntime: FATAL EXCEPTION: main
08-21 11:07:07.920 22644 22644 E AndroidRuntime: Process: de.ccc.events.badge.card10, PID: 22644
08-21 11:07:07.920 22644 22644 E AndroidRuntime: java.lang.IllegalStateException
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at de.ccc.events.badge.card10.common.ConnectionService.connect(ConnectionService.kt:67)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at de.ccc.events.badge.card10.filetransfer.FileTransferFragment.initConnection(FileTransferFragment.kt:85)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at de.ccc.events.badge.card10.filetransfer.FileTransferFragment.onViewCreated(FileTransferFragment.kt:79)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1471)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at androidx.fragment.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1784)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1852)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at androidx.fragment.app.BackStackRecord.executeOps(BackStackRecord.java:802)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at androidx.fragment.app.FragmentManagerImpl.executeOps(FragmentManager.java:2625)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at androidx.fragment.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2411)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at androidx.fragment.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2366)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at androidx.fragment.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2273)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at androidx.fragment.app.FragmentManagerImpl$1.run(FragmentManager.java:733)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at android.os.Handler.handleCallback(Handler.java:873)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at android.os.Handler.dispatchMessage(Handler.java:99)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at android.os.Looper.loop(Looper.java:193)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at android.app.ActivityThread.main(ActivityThread.java:6718)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at java.lang.reflect.Method.invoke(Native Method)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
08-21 11:07:07.920 22644 22644 E AndroidRuntime: 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
08-21 11:07:07.928  6130  6204 W ActivityManager:   Force finishing activity de.ccc.events.badge.card10/.MainActivity
08-21 11:07:07.937  6130  6313 I ActivityManager: Showing crash dialog for package de.ccc.events.badge.card10 u0
08-21 11:07:07.980  6130  9843 I OpenGLRenderer: Initialized EGL, version 1.4