Part cooling fan always on

I got to powering up my ratrig and I noticed my 4028 Nidec fan spins up immediately and doesn't turn off. I followed the build guide and connected the pos/neg wires to the always on fan port of my motherboard (octopus 1.1), and the pwm (blue) wire to the bottom fan port as instructed. I also have a fourth wire coming out of the fan (yellow iirc) but didn't use it as nothing is mentionedcabout it. What could be my issue?