(adsbygoogle = window.adsbygoogle || []).push({}); i wanted to downgrade from 4.21 using rogero downgrader so what what i did was.

While on CFW i went to System Update from XMB and install the 4.xx Downgrader PUP.

After the 4.xx Downgrader PUP installs i was on a hybrid CFW 3.55 shows that i am still on 4.21

i Ran the "Rebug Toggle QA" from XMB, the screen went black and heard 2 or 3 Beeps and the PS3 restart back to the XMB.

i made sure that QA Flag was set, i went to "Network Settings" then pressed:
L1 + L2 + L3 (press left stick) + R1 + R2 + dpad_down

4) i put the Rogero CEX-3.55 CFW V3.7 on my usb and used the System Update from XMB.

5) Now i get error 8002F157 no matter what i do. am i bricked/stuck? is there a solution?

It would have been better if you did it before using the downgrader .PUP... but too late now haha try installing it through recovery menu, and post back with results.