Hi,
Did you ask the previous owner how he was housing/ feeding her?
Maybe he did something unusual and she got used to that. Does she eat if you leave an F/T in her tub overnight?
I have a big female that was (is ) extremely nervous and never really calmed down. She would only ever eat if it was shown to her from no closer than a foot then laid quietly on the floor of the tub and the tub then closed gently.
If anything spooked her at all she just refused to eat. It took laying a clutch of eggs to get her into a strong enough feeding mode to strike feed - but she still needs to be left alone immediately after the strike.
dr del