Barry,
Your AC card number may still be in the system.
I had two accounts until recently having them combined while at the Tunica chip show. Ask at the club booth for them to check for other accounts the next time you visit a Harrah's.
On reisues, Harrah's will give a card with the current account number (usually the original issue location) or if you have multiples the first one the attendant finds in the database. That is why the first 3 positions of a card number do not mean the card is "from" a particular Harrah's Casino / location. I have had reissues from at least 8 Harrah's locations all with my original AC card number. The only thing the first 3 positions signify is where that "account" was opened not necessarily where the "card" was issued.

Paul