null pointer exception when using route helper assistant

[Polyglot]

What steps will reproduce the problem?

1. I had used it for the opposite direction just before
2. Now I added the first way to this way of travel and actived the routing helper

What is the expected result?

What happens instead?

Please provide any additional information below. Attach a screenshot if possible.

URL:https://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2018-07-24 01:20:01 +0200 (Tue, 24 Jul 2018)
Build-Date:2018-07-24 02:23:01
Revision:14046
Relative:URL: ^/trunk

Identification: JOSM/1.5 (14046 en) Linux Mint 18.3 Sylvia
Memory Usage: 1626 MB / 2267 MB (457 MB allocated, but free)
Java version: 1.8.0_171-8u171-b11-0ubuntu0.16.04.1-b11, Oracle Corporation, OpenJDK 64-Bit Server VM
Screen: :0.0 1600x900
Maximum Screen Size: 1600x900
Java package: openjdk-8-jre:amd64-8u171-b11-0ubuntu0.16.04.1
Dataset consistency test: No problems found

Plugins:
+ Mapillary (v1.5.15)
+ OpeningHoursEditor (34389)
+ apache-commons (34389)
+ apache-http (34389)
+ buildings_tools (34212)
+ ejml (34389)
+ geotools (34125)
+ jts (34206)
+ measurement (34206)
+ opendata (34389)
+ pt_assistant (306)
+ reverter (34271)
+ scripting (30785)
+ tag2link (34109)
+ terracer (34109)
+ todo (30305)
+ utilsplugin2 (34389)
+ wikipedia-dev (v1.0.1-43-gb77c0c5)

Tagging presets:
+ https://josm.openstreetmap.de/josmfile?page=Presets/BENELUX&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Presets/Trees&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Presets/OneClick&zip=1

Map paint styles:
+ https://josm.openstreetmap.de/josmfile?page=Styles/PublicTransport&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/NumberedCycleNodeNetworks&zip=1

Last errors/warnings:
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- E: Handled by bug report queue: java.lang.NullPointerException


=== REPORTED CRASH DATA ===
BugReportExceptionHandler#handleException:
No data collected.

Warning issued by: BugReportExceptionHandler#handleException

=== STACK TRACE ===
Thread: AWT-EventQueue-0 (18) of main
java.lang.NullPointerException
	at org.openstreetmap.josm.plugins.pt_assistant.actions.MendRelationAction.getNextWayAfterSelection(MendRelationAction.java:1481)
	at org.openstreetmap.josm.plugins.pt_assistant.actions.MendRelationAction$2.keyPressed(MendRelationAction.java:1142)
	at java.awt.Component.processKeyEvent(Component.java:6491)
	at javax.swing.JComponent.processKeyEvent(JComponent.java:2832)
	at java.awt.Component.processEvent(Component.java:6310)
	at java.awt.Container.processEvent(Container.java:2238)
	at java.awt.Component.dispatchEventImpl(Component.java:4889)
	at java.awt.Container.dispatchEventImpl(Container.java:2296)
	at java.awt.Component.dispatchEvent(Component.java:4711)
	at java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1954)
	at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(DefaultKeyboardFocusManager.java:835)
	at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(DefaultKeyboardFocusManager.java:1103)
	at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:974)
	at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:800)
	at java.awt.Component.dispatchEventImpl(Component.java:4760)
	at java.awt.Container.dispatchEventImpl(Container.java:2296)
	at java.awt.Window.dispatchEventImpl(Window.java:2746)
	at java.awt.Component.dispatchEvent(Component.java:4711)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760)
	at java.awt.EventQueue.access$500(EventQueue.java:97)
	at java.awt.EventQueue$3.run(EventQueue.java:709)
	at java.awt.EventQueue$3.run(EventQueue.java:703)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:90)
	at java.awt.EventQueue$4.run(EventQueue.java:733)
	at java.awt.EventQueue$4.run(EventQueue.java:731)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:730)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)