You can prevent certain customers from ordering from your store with the help of our free Fraud Filter app.
You can learn more about the app and how it works here.
Hope this helps!
Sorry to hear about your chargebacks. Shopify has a "disable account" feature if you require all customers to create an account before purchase. Other than this option, there are no other native means to stop a customer from making a purchase. As @Elle has mentioned, you can use the fraud filter app to ban the customer by IP address or home address from making a repeat purchase.
Keep in mind that this does not stop them from making a new account and making another purchase.
I hope this helps.