You can absolutely either disable a customer account or delete it.

1. Disable a customer account

1. From the app admin page, find Wholesaler Registration Form
2. Click Registration Management 
3. Click Delete icon of the customer you want to restrict
4. Hit Disable this customer (Shopify -> Disable account)
   

5. You'll be redirected to this customer account page > click Disable account

2. Delete a customer account on Shopify

1. From the app admin page, find Wholesaler Registration Form
2. Click Registration Management 
3. Click Delete icon of the customer you want to restrict
4. Hit Delete this customer on ShopifyResult: This customer will be deleted in Shopify admin page > Customers.

3. Delete a customer account on app server

1. From the app admin page, find Wholesaler Regsitration Form
2. Click Registration Management 
3. Click Delete icon of the customer you want to restrict
4. Hit Delete this customer on our app server

Result: This customer will be deleted from the Registered Customers grid above.

4. Delete a customer account on both

1. From the app admin page, find Wholesaler Regsitration Form
2. Click Registration Management 
3. Click Delete icon of the customer you want to restrict
4. Hit Delete this customer on both

Result: This customer will be deleted from Shopify admin page > Customers and the Registered Customers grid above.