You can’t wait and perform actions at the same time, so that won’t work for you. in this case
I made a workflow for you. All you need to do is substitute a unique ID and add your logic in the middle.
This saves a file on your system with the name of the ID then deletes the file when the workflow is done. The first step checks if the file already exists, which is the check if it is already running as it will not exist if it is not running.
I put some effort into explaining in the workflow as I have seen others request this as well, hopefully this is helpful to them as well.
Let me know if you have any questions
Edit: See the workflow here for self hosted and here for cloud.