Upward Movement?

So I want my character to be able to move forward, backward, side to side, and up and down. Right now I can move forward and backwards and side to side but every time i try to move up with the key i bound it doesn’t move up but I can see that it is trying to move in the direction up but not leaving the ground. For instance, when I look down and the top of the character is facing forwards, the direction “up” is forwards, and the character moves forwards. When my character looks at the sky the direction up is behind and holding my bound up key will move him backwards. But when i look forwards and the direction up is towards the sky, my character never leaves the ground. Essentially there is no movement in the z axis.

How is your movement code setup?