Plant Problems. Need help with a Jack 47

This Jack 47 is about 2 months old now and I've ran into some problems. Is this plant salvageable? I have burned her once before so i have been reluctant to over feed. Please help.

Looks old and tired. Give her some superthrive if you have access to any. She needs her some health supplement.

are there any alternatives to it if i can't get superthrive?