*Moved to help section*
We need to know what your PS3 is (for example CECH-3003B: can be found on the back or underside of the console)
Run minvercheck in my sig and report back the MIN version the app tells you your PS3's can downgrade to.
If neither can downgrade to 3.55, you are sh!t out of luck.
If one or both can be downgraded, you will need to buy hardware flasher such as E3, progskeet or teensy++, and a FSM/downgrade dongle.