Cornet MM has a fixed gain of 44dB. You can't change it, as both passive EQ and gain are tied to 12AX7 parameters. It is what it is.
https://www.haglabs.com/collections/phono-preamps/products/cornet-mm-vacuum-tube-phono-preamp
If you need 64dB gain at 47k loading, Bugle MC? Trumpet MC can do 74dB at 47k load...