Bulk Discounts uses Shopify's Discount API which is an unstable API, especially under heavy load.
If your set is stuck, Bulk Discounts will try to finish creating it over the next hour. There is no need to contact us just yet - please wait for the set to finish (because it definitely will). If it cannot finish creating the entire set, it will show you how many codes were created and tell you there was an error.
In this case, you will need to create a new set of codes to finish the ones that were not created.
If you want a credit, reach out to us at firstname.lastname@example.org and we will sort one out for you. Please provide examples and the discount set name(s) so we can expedite your support.