Hi,
I have a little normal female here I have been assisting as needed for just over a year.
I had got her to strike feed 4 times in July then she stopped again and I was seriously thinking of just giving up on her.
But she struck and ate a huge ( for her as shes only around 150g ) rat two weeks or so ago, went into a shed and struck fed on another rat ( more appropriately sized ) just three days ago.
The point of all this rambling being....
It can take a while for them to start, but if you really want to keep her then keep her. You can change her substrate and tub size etc if you want to try that rather than just sell her and hope it helps.
Just remember if you do sell her then the buyer will have to deal with the problems and may be unhappy about it and pass his feedback on to others. He may forget to mention he bought her cheaply as a non-feeder however.
dr del