How can I create a Mail-Reminder on an Event-Based Gateway?

I want to send E-Mail reminder to a user while I am waiting for a Message to continue the Workflow. This Part is currently modelled like this:

As you can see, I am using an "Event-Based Gateway" to decide between two Messages. In addition, I use a "Timer Intermediate Catch Event" with the type cycle to fire, e.g. every 10 Minutes. The Task "Approval Person erinnern" is an external Task which handles mail delivery.

The Problem I am having is that I have to leave the "Event-Based Gateway" to send a reminder Mail. While I am waiting for my External Task Worker to finish the "Approval Person erinnern" task, I can't receive the messages I am waiting for. In my Use case, sending a reminder Mail and received one of the defined messages could happen parallel.

Any idea how I could change my model Diagram to achieve my Goal?

I am using Camunda Platform 7.19

I tried to use the Asynchronous continuations feature but did not have any luck with it.

This should work. The main flow in the embedded sub-process stays active until either "genehmigt" or "abgelehnt" message arrives, via the non-interrupting intermediate timer you trigger the email reminder.