Thumb problems on a komatsu

I have a Komatsu PC 75 uu-2. I bought a thumb for it and I installed it I have all of the hydraulic lines heading out to the end for the thumb in the pedal inside. The machine used to be set up for a rock hammer. Now I am finding that if I go to the left with the pedal it is high speed into the right of the pedal is low speed on the same hose. Does anyone know how I can make it so it flows both ways