Be sure the grind knob is turned to the finest setting.

Use a permanent marker to make alignment marks on the three parts of the gear assembly. The marks should line up during reassembly.

There are 4 plastic tabs radially holding the big white gear assembly in place. I used both hands, placing my finger tips under each side of the big gear and pulled straight up to remove it.

If pulling straight up isn't working, try curling your fingers under just one side of the white gear, and prying upwards until that side pops free a little. Then do the other side.