ps3 slim bricked forgot to dehash Help guyz

Dear people,

i just bricked my ps3 slim- CECH-2504b

i was able to update my e3 flasher - succes

i was able to make a backup from my nor 3 times and it looked good - succes

i was able to do a restore process from the backup i made from my nor - succes

i was able to do the downgrade process - succes

in short i did everthing good i had rogero 3,7 on my ps3 and through the recovery menu i flashed 3,55 ofw
and suddenly the ps3 turny off. As you can see i forgot to dehash my ps3 when i had rogero 3,7.

Now the ps3 wont turn i mean every time i want to turn on it goes off wihtin 3 a 5 sec without any sound.