1) Update your jailbreak.
See:
https://www.mobileread.com/forums/sho...d.php?t=186645 for information, include reading the section for people with firmware greater than 5.6.x (that is you).
See:
https://www.mobileread.com/forums/sho...postcount=1597 for using the hotfix (which is what you need to do).
For all other packages, check here first:
https://www.mobileread.com/forums/sho...d.php?t=225030
2) Install KUAL
3) Install MrPI
MrPI (Mobileread Package Installer) is a KUAL menu extension, so you need KUAL to run it.
You
**MUST** use MrPI to install or re-install packages on your new firmware.
Get that much done and post back if you are still having trouble.
(We do expect people who own an e-book reading device to be able to read the directions.)
NOTE: Double posting is really, really frowned on here.