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Daniela, you said "I first registered with AFF in Sydney". Now by using this term AFF, do you mean "Australian Frequent Flyer" (this discussion group) or "Ansett Frequent Flyer" (the now very dead frequent flyer program here in Australia.
If you mean the former, thadocta's response is correct - which FF program are they in? If you mean the latter, say goodbye to the points...they're dead and don't look like being resurrected.