Spark Call Estblishing Problem

Hi

i am using spark 2.5.8 when i trying to call useing Computer to computer i got blow error…

SessionClose Remotly…

& i attached sreeshot of that error…

java.util.MissingResourceException: Can’t find resource for bundle java.util.PropertyResourceBundle, key tooltip.place.a.call
at java.util.ResourceBundle.getObject(ResourceBundle.java:386)
at java.util.ResourceBundle.getString(ResourceBundle.java:346)
at org.jivesoftware.resource.Res.getString(Res.java:37)
at org.jivesoftware.sparkimpl.plugin.phone.PhonePlugin$3.chatRoomOpened(PhonePlugi n.java:154)
at org.jivesoftware.spark.ui.ChatContainer.fireChatRoomOpened(ChatContainer.java:8 23)
at org.jivesoftware.spark.ui.ChatContainer.addChatRoom(ChatContainer.java:302)
at org.jivesoftware.spark.ChatManager.createChatRoom(ChatManager.java:218)
at org.jivesoftware.spark.ChatManager.handleJID(ChatManager.java:875)
at org.jivesoftware.spark.ChatManager.handleURIMapping(ChatManager.java:813)
at org.jivesoftware.SparkStartupListener.startupPerformed(SparkStartupListener.jav a:25)
at com.install4j.api.launcher.StartupNotification$ListenerAdapter.startupPerformed (Unknown Source)
at com.exe4j.Controller$StartupThread$1.run(Unknown Source)