If your shopper is saying that they were charged, but you don't see any record of their order in your e-commerce platform or within your Sezzle account (under the "Orders" page), they're likely seeing a pre-authorization charge, which is just a temporary hold on the funds.

It can be at times that the transaction had failed and the amount will automatically refund to the customer’s account within 3-5 business days. 

For further details, we request you to please contact us at merchantsupport@sezzle.in with the customer's email address and registered phone number.