Tomw1495

The bottom knob is a hex fit but the top one of the stacked pot doesn't have a hex screw, I pulled it out like a press fit when I took it apart so that's why I'm confused as to why it's not fitting back together

So I took the stacked mid pot knobs off of my sire v7 cause the pots were a little crackly, so I cleaned it but now I can't seem to get the top knob back into place, the bottom one is back in the rail and fitting into the notched section as normal, just can't get the top knob back into the right place? Any ideas on how I can fix this?