Why is my psp not recognize the games after upgrade my psp to 6.00

Because you are using an Official Firmware(OFW) try
downgrading to a 5.00M33-6 Custom firmware(CFW)
you can easily do this with a pandora battery which will install 5.00 OFW on your psp and then you simply download the 5.00m33-6 CFW update
OR
download
1. Hellcat's Recovery Flasher
2. 5.00 OFW it is 25.83MB

install the Hellcat's Recovery Flasher on the psp
and put the 5.00 OFW on the psp
This files should be put in this directory
PSP/GAME

open the Hellcat's Recovery Flasher in the memory- stick of the Game section when the psp is on

follow the instructions
ENJOY..!!