Hey ! I had the same issue with mine. She would only eat snails and bloodworms. So the best method I have found doesn’t sound the best, but it works. I didn’t feed mine for 2 days and then tried shrimp, it worked very well. I was also told they can go about a week without eating. Hope this helps ??
Nothing wrong with starving a fish for a few days and if you think about them in nature, they may go weeks without food...