Kyocera FS 1900 peristent jamming

I have a Kyocera FS 1900 laser printer that is persistently jamming.

I have removed the paper feed unit and cleaned all the rollers, the problem persists.

It always ‘jams’ it appears, as the donor has been transferred to the paper, as if it’s getting stuck or blocked from moving to the out-tray.

Any ideas?

Thanks.