Customer purchased images but I didn't receive payment via Paypal

Hi, I received notification 3 days ago saying a customer ordered images but I haven’t received the actual payment even though it says the payment went thru with Paypal. I realized today I had the payment settings checkbox on “sandbox” rather than “live”–I just switched it now. I have an order number for the payment that was made by the customer but since the payment was never actually received does he have to put the payment through again now that I have it set on “Live” or will the payment go through automatically now? I’d hate to have to bother my customer with this. Thanks.