Low stock emails can be set on the Product Option level.
See how to do get notified re. stock in the help page linked below,
Create a Product, Product Price, and Stock Configuration
Learn how to create products, set prices, and manage stock configurations effectively in our guide. Streamline your sales process with step-by-step instructions.
By default, low stock emails go to your gym’s contact email address.
You can override this on the settings page.