[How to received funds from a failed marketplace transaction]

An object was sold to a customer of mine through the marketplace, I never received the funds from that transaction and she never received the object although the purchase price of the object was deducted from her account, so I delivered the product to her in world, at cost to myself. What  steps should I take to correct the situation

[Geoforce GT230 Graphics Card]

wondering if that is the problem with my old laptop...it got to where it would get hot and shut off...i would have to let it cool down and then restart the laptop...now it only comes on for a couple of minutes where you can see the desktop screen..then lines go through the lcd screen where you cannot see the desktop anymore then it shuts its self off..and tries to reboot several times but is unsuccessful