Retry for child workflows should execute parallel

we are running child workflows parallel to execute some task, for that we added “Promise result = Async.function()” and Promise.allOf(results).get() to do the parallel execution of child workflows. It’s working as expected but when i added retry to child workflows to make child workflows to fail in case of specific exception and updated this “Promise.allOf(results).get()” to -> {
                    try {
                    } catch (Exception e) {
                        Throwable cause = e.getCause();
                        if (cause instanceof MMLCommandExecutionException) {
                            log.error("Child workflow failed: {}", cause.getMessage());
                        } else {
                            throw new RuntimeException("Child workflow failed: {}", e.getMessage())

to handle the Exception. Now these retry child workflows are not executing parallel, its executing one by one(once completed the max retry). Any idea how to execute it parallel?

Can you post a history of an example of when these workflows are executed one by one?