What is the problem?
Octoprint stopped working after I tried to flash Prusa firmware from .hex file.
What did you already try to solve it?
reboot, tried to connect to pi but I cant remember my password 
Logs (octoprint.log, serial.log or output on terminal tab at a minimum, browser error console if UI issue ... no logs, no support!)
Additional information about your setup (OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... as much data as possible)