From time to time my application crash in http2 release part

I can't reproduce this. I only have stacktrace from breakpad

Crash reason: EXCEPTION_ACCESS_VIOLATION_READ
Crash address: 0xffffffffffffffff

0 Qt5Network.dll!QHash<unsigned int,Http2::Stream>::detach() [qhash.h : 291 + 0xc]
1 Qt5Network.dll!QHttp2ProtocolHandler::handleConnectionClosure() [qhttp2protocolhandler.cpp : 215 + 0xc]
2 Qt5Network.dll!QHttpNetworkConnectionChannel::_q_error(QAbstractSocket::SocketError) [qhttpnetworkconnectionchannel.cpp : 991 + 0x10]
3 Qt5Network.dll!QHttpProtocolHandler::_q_readyRead() [qhttpprotocolhandler.cpp : 236 + 0x14]
4 Qt5Core.dll!doActivate<0>(QObject *,int,void * *) [qobject.cpp : 3882 + 0xa]
5 Qt5Network.dll!QAbstractSocketPrivate::emitReadyRead(int) [qabstractsocket.cpp : 1307 + 0x9]
6 Qt5Network.dll!QReadNotifier::event(QEvent *) [qnativesocketengine.cpp : 1277 + 0x9]
7 Qt5Widgets.dll!QApplicationPrivate::notify_helper(QObject *,QEvent *) [qapplication.cpp : 3685 + 0xc]
8 Qt5Widgets.dll!QApplication::notify(QObject *,QEvent *) [qapplication.cpp : 3639 + 0xe]
9 Qt5Core.dll!QCoreApplication::notifyInternal2(QObject *,QEvent *) [qcoreapplication.cpp : 1075 + 0x13]
10 Qt5Core.dll!qt_internal_proc(HWND__ *,unsigned int,unsigned _int64,_int64) [qeventdispatcher_win.cpp : 209 + 0xd]

I use haproxy on server

I don't have any crash reports when I don't enable http2