grails 3.3.0 , java 8 , default url

ERROR org.grails.plugins.rx.web.RxResultSubscriber - Async Dispatch Error: No signature of method: grails.rx.web.helper.RxHelper.event() is applicable for argument types: (java.util.LinkedHashMap, grails.converters.JSON) values: [[id:0, comment:hello], {"type":"observable","num":0}]
Possible solutions: event(groovy.lang.Closure), event(groovy.lang.GString), event(groovy.lang.Writable), event(java.lang.CharSequence), event(java.util.Map), event(org.codehaus.groovy.runtime.GStringImpl)
groovy.lang.MissingMethodException: No signature of method: grails.rx.web.helper.RxHelper.event() is applicable for argument types: (java.util.LinkedHashMap, grails.converters.JSON) values: [[id:0, comment:hello], {"type":"observable","num":0}]
Possible solutions: event(groovy.lang.Closure), event(groovy.lang.GString), event(groovy.lang.Writable), event(java.lang.CharSequence), event(java.util.Map), event(org.codehaus.groovy.runtime.GStringImpl)
at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.unwrap(ScriptBytecodeAdapter.java:58)
at org.codehaus.groovy.runtime.callsite.PogoMetaClassSite.call(PogoMetaClassSite.java:54)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:133)
at rxjava.demo.TickTockController$_observable_closure5.doCall(TickTockController.groovy:75)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.springsource.loaded.ri.ReflectiveInterceptor.jlrMethodInvoke(ReflectiveInterceptor.java:1426)
at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:93)
at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:325)
at org.codehaus.groovy.runtime.metaclass.ClosureMetaClass.invokeMethod(ClosureMetaClass.java:294)
at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1024)
at groovy.lang.Closure.call(Closure.java:414)
at rxjava.demo.TickTockController$_observable_closure5.call(TickTockController.groovy)
at org.codehaus.groovy.runtime.ConvertedClosure.invokeCustom(ConvertedClosure.java:54)
at org.codehaus.groovy.runtime.ConversionHandler.invoke(ConversionHandler.java:124)
at com.sun.proxy.$Proxy98.apply(Unknown Source)
at io.reactivex.internal.operators.observable.ObservableMap$MapObserver.onNext(ObservableMap.java:59)
at io.reactivex.internal.operators.observable.ObservableDoOnEach$DoOnEachObserver.onNext(ObservableDoOnEach.java:103)
at io.reactivex.internal.observers.DisposableLambdaObserver.onNext(DisposableLambdaObserver.java:58)
at io.reactivex.internal.operators.observable.ObservableInterval$IntervalObserver.run(ObservableInterval.java:83)
at io.reactivex.internal.schedulers.ScheduledDirectPeriodicTask.run(ScheduledDirectPeriodicTask.java:39)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)