[Tug]

Today in the morning I added a 417 mb PDF file to my kindle after that when I turned on the kindle everything was gone including kual,mrpi basically everything including books the only think remaining is a blank document folder and a system folder besides that kindle is full of hundred of really small files with unknown extension and weird names.
now I really don't know what happened maybe I corrupted everything inside somehow.
I added few PDFs into document folder just to check whether its working or not unfortunately it wasn't I was using koreader and it's gone now and the native one isn't working.screen just goes blank for a second and then sends me to back to main menu.
I want to know what can I do? I can't factory reset because my kindle is jailbroken and I don't want to loose jailbreak otherwise I would have done that.is it ok for me to delete everything inside kindle including system folder?is the jailbreak and hotfix gone do I need to install everything again

PS-my kindle is kt3 firmware version 5.8.7