Springboot ThreadPoolTaskScheduler doesnt wait for my tasks to finish before shutting down

I created a SpringBoot 2.4.2 application that has several long running tasks that should not be terminated while they are still running.

I have defined the Scheduler like this:

@Configuration
public class SchedulerConfig implements SchedulingConfigurer {

    @Override
    public void configureTasks(ScheduledTaskRegistrar taskRegistrar) {
        ThreadPoolTaskScheduler scheduler = new ThreadPoolTaskScheduler();

        scheduler.setPoolSize(10);
        scheduler.setThreadNamePrefix("my-scheduled-task-pool ");
        scheduler.setAwaitTerminationSeconds(30);
        scheduler.setWaitForTasksToCompleteOnShutdown(true);
        scheduler.initialize();

        taskRegistrar.setTaskScheduler(scheduler);
    }
}

Then I have an @Service class in a seperate package that contains a method like this:

@Scheduled(fixedDelay = 5000)
    public void myTask() {
        someLongRunningTask();
        System.out.println("Finished Task")
    }

When I terminate the Program by either doing CTRL+C in the Terminal or calling kill -15 {$pid}, spring shuts down before the myTask() method is finished.

Is there a way I can force Spring to always wait for all of my Tasks to finish before Shutting down? I was under the assumption that scheduler.setWaitForTasksToCompleteOnShutdown(true) took care of this.

Thanks a lot for your help