Feed not generating

At the first build, when there are no cache files yet – from 3 minutes to 30. It depends on the server and the number of products.
In the presence of cache files – 5-30 seconds.
See this:

And this:
https://icopydoc.ru/en/how-to-create-an-xml-feed-in-woocommerce-for-google-merchant-center-instruction/

Important! The plugin needs a working WP-cron!
Most likely your sitehas disabled wp_cron.
If you use server cron:
Create a task on the server so that the wp-cron.php file runs regularly.
After that, the xml-feed will be successfully created.