I have rooted my Straight Talk Samsung Galaxy Grand Prime (SM-S920L) running with Android 5.0 and while trying to load TWRP recovery I messed up with my device and now, I can only get into download mode. It says "Set warranty bit : kernel". Samsung's website doesn't list my device and it turns out to be a model Samsung makes for the TracFone network, so I am at a dead end. Using Odin I have tried other firmware with no luck and Samsung Kies is also of no use.
What can I do now to get my phone working again?