HP P3005x jam under cartridge

My old P3005 always jam under cartridge after my sister used it for a few years and returned it to me. I tried to fix it by myself, but I don't know which parts I should replace. Can anyone give me some hints? Is it a fuser problem? Or should I try a new cartridge?

Following youtube link shows the jam:

https://youtu.be/nvt-ejBR0o4

Thanks for any help.