signal event not fired

[hamid_gholipour]

Hello
recently i've come across a problem with firing signal events. Correspondig to the following example ,i want a catch signal event and a timer be placed after a gateway event in which the catch signal event be fired through an execution of a system task .  the class in which the firing logic was written is as below :
public class Test  implements JavaDelegate{
   ProcessEngine processEngine;
   public Test() {
       processEngine = ProcessEngineConfiguration
             .createStandaloneProcessEngineConfiguration()
             .setDatabaseType("postgres").setJdbcUsername("XXXXX")
             .setJdbcPassword("XX")
             .setJdbcUrl("jdbcostgresql://XXXXX:5432/XXX")
             .buildProcessEngine();
   }

   @Override
   public void execute(DelegateExecution execution) throws Exception {
      RuntimeService runtimeService = this.processEngine.getRuntimeService();
       runtimeService.signalEventReceived("alertSignal");
   }

}

is there any advice on how i can work with signal events ? what is more my activiti version in 5.15 .
thank you in advance

[jbarrez]

Try using the name instead of id. ie. use 'alert' instead of 'alertSignal'