Are you using the stock PBG MM pup or something else?

The stock pup is usually shipped with the red and white series link joined, so it works as a series humbucker rather than the traditional parallel MM. If you want to follow the PBG diagram you’ll need to separate the joined red and white tips, then connect black to the 1st volume, red to the 2nd volume, and white & green & bare to ground on the the back of the pot.