Client crash on joining.

I’m trying to learn unreal engine networking and make small project for that purpose, but something fail.
This is how I create session.

This is how I find session

This is how I join

Where InitGameEntry save BluePrintSessionResult in widget and when come times for joining I use the same result.
When I click join my client crash with that stacktrace:

Unknown exception - code 00000001 (first/second chance not available)

Fatal error: [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.6\Engine\Source\Editor\UnrealEd\Private\Editor.cpp] [Line: 6896]
World //Game//Maps//UEDPIE_0_MenuMap.MenuMap not cleaned up by garbage collection!
(Object is not currently ro

KERNELBASE + 35740 bytes
UE4Editor_Core + 3092349 bytes
UE4Editor_Core + 1597391 bytes
UE4Editor_UnrealEd + 1817658 bytes
UE4Editor_Engine + 9510791 bytes
UE4Editor_Engine + 9261061 bytes
UE4Editor_Engine + 9613469 bytes
UE4Editor_UnrealEd + 1802106 bytes
UE4Editor_UnrealEd + 6686342 bytes
UE4Editor!FEngineLoop::Tick() + 3876 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.6\engine\source\runtime\launch\private\launchengineloop.cpp:2214]
UE4Editor!GuardedMain() + 479 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.6\engine\source\runtime\launch\private\launch.cpp:131]
UE4Editor!GuardedMainWrapper() + 26 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.6\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!WinMain() + 249 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.6\engine\source\runtime\launch\private\windows\launchwindows.cpp:202]
UE4Editor!__tmainCRTStartup() + 329 bytes [f:\dd\vctools\crt\crtw32\dllstuff\crtexe.c:618]

I also add this to DefaultEngine.ini:

Any idea what I’m doing wrong and what is the correct way ??