Now that she's eaten once, I would maybe try feeding her prey items that are fair sized for her, but maybe a touch smaller than you would normally feed so that you don't put her off by offering too big an item and also to kind of ensure that she's a little more hungry at the next meal until she's eating steadily, then move her back up to normal size prey. I'd say try feeding every 7 days, that way it isn't too long between feedings but it isn't very often either. She seems like she's fairly young by the length you've given (though it's hard to tell just by length) so after she's started eating steadily then maybe start to offer her food every 5 days until she's regained some weight that she might have lost.
Just my $0.02![]()