13:30:43,225 ERROR [org.kie.server.remote.rest.jbpm.UserTaskResource] (default task-1) Unexpected error during processing null: java.lang.NullPointerException
	at org.jbpm.services.task.commands.CompleteTaskCommand.execute(CompleteTaskCommand.java:75)
	at org.jbpm.services.task.commands.CompleteTaskCommand.execute(CompleteTaskCommand.java:39)
	at org.jbpm.services.task.commands.CompositeCommand.execute(CompositeCommand.java:144)
	at org.jbpm.services.task.commands.TaskCommandExecutorImpl$SelfExecutionCommandService.execute(TaskCommandExecutorImpl.java:76)
	at org.jbpm.services.task.commands.TaskCommandExecutorImpl$SelfExecutionCommandService.execute(TaskCommandExecutorImpl.java:63)
	at org.drools.core.command.impl.AbstractInterceptor.executeNext(AbstractInterceptor.java:39)
	at org.jbpm.services.task.persistence.TaskTransactionInterceptor.execute(TaskTransactionInterceptor.java:69)
	at org.jbpm.services.task.persistence.TaskTransactionInterceptor.execute(TaskTransactionInterceptor.java:45)
	at org.drools.core.command.impl.AbstractInterceptor.executeNext(AbstractInterceptor.java:39)
	at org.drools.persistence.jta.TransactionLockInterceptor.execute(TransactionLockInterceptor.java:73)
	at org.drools.persistence.jta.TransactionLockInterceptor.execute(TransactionLockInterceptor.java:45)
	at org.drools.core.command.impl.AbstractInterceptor.executeNext(AbstractInterceptor.java:39)
	at org.drools.persistence.jpa.OptimisticLockRetryInterceptor.internalExecute(OptimisticLockRetryInterceptor.java:102)
	at org.drools.persistence.jpa.OptimisticLockRetryInterceptor.execute(OptimisticLockRetryInterceptor.java:83)
	at org.drools.persistence.jpa.OptimisticLockRetryInterceptor.execute(OptimisticLockRetryInterceptor.java:44)
	at org.drools.core.runtime.InternalLocalRunner.execute(InternalLocalRunner.java:37)
	at org.drools.core.runtime.InternalLocalRunner.execute(InternalLocalRunner.java:41)
	at org.jbpm.services.task.commands.TaskCommandExecutorImpl.execute(TaskCommandExecutorImpl.java:47)
	at org.jbpm.services.task.impl.command.CommandBasedTaskService.complete(CommandBasedTaskService.java:172)
	at org.jbpm.runtime.manager.impl.task.SynchronizedTaskService.complete(SynchronizedTaskService.java:119)
	at org.jbpm.kie.services.impl.UserTaskServiceImpl.complete(UserTaskServiceImpl.java:189)
	at org.kie.server.services.jbpm.UserTaskServiceBase.complete(UserTaskServiceBase.java:97)
	at org.kie.server.remote.rest.jbpm.UserTaskResource.complete(UserTaskResource.java:123)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.jboss.resteasy.core.MethodInjectorImpl.invoke(MethodInjectorImpl.java:139)
	at org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTarget(ResourceMethodInvoker.java:295)
	at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:249)
	at org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:236)
	at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:402)
	at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:209)
	at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:221)
	at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:56)
	at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:51)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
	at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:85)
	at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62)
	at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36)
	at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:131)
	at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57)
	at io.undertow.server.handlers.DisableCacheHandler.handleRequest(DisableCacheHandler.java:33)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at io.undertow.security.handlers.AuthenticationConstraintHandler.handleRequest(AuthenticationConstraintHandler.java:51)
	at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46)
	at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64)
	at io.undertow.servlet.handlers.security.ServletSecurityConstraintHandler.handleRequest(ServletSecurityConstraintHandler.java:59)
	at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60)
	at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77)
	at io.undertow.security.handlers.NotificationReceiverHandler.handleRequest(NotificationReceiverHandler.java:50)
	at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
	at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:285)
	at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:264)
	at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81)
	at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:175)
	at io.undertow.server.Connectors.executeRootHandler(Connectors.java:207)
	at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:802)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)