I cannot flash stock rom in my galaxy note 2(n7100)

[AC Question]

hii...i flashed cynagonmod rom 13 with android 6.0.Nw my phne is not working.i can access download mode.i tried to flash stock rom using odin and it says failed.....what can i do..plz help...i am very afraid....when i turn on my phne it says firmware upgrate problem.....