So you know...under system settings it will always say 3.55 regardless if your running Geohot CFW or any of the other released ones. If you want to return your ps3 to normal.
Go to Sony.com download the official 3.55 OFW. Put in on a flash drive. On the root of the USB make a folder called PS3 --> UPDATE ---> then put the OFW from sony's website. It should be called PS3UPDAT.PUP
Again Flash Drive...Root Folder PS3 ---> UPDATE ---> PS3UPDAT.PUP
Now just go to update firmware by usb and it should work...if not try to do it in recovery mode.
Make sure you delete all your CFW packages as well if you are worried about getting banned