Just thought of something else that happened to me a few years ago.

Someone in Russia used one of my cc # to buy porn-about $40 worth. ATT canceled the card and credited my account. I received no other credit on the transaction.

4 YEARS later (about 2 years ago), I received a letter from a company in San Francisco saying I reported a fraudlent charge on my card four years earlier and that ATT AND this company (supposedly the company selling the porn) had both credited my account, "resulting in a double credit". The SF company threatened me with legal action if I didn't send them the $40 in question.

I went back and got copies of my statements, even though I knew this company was lying, just in case. Then I ignored them.

Haven't heard a word since.

My advice: Keep all paperwork related to the fraud for a LONG time.