Character will not move vertically with camera direction

To clarify; the player model itself can tilt up and down, the player position however remains locked on the horizontal axis it was placed on. This defeats the entire purpose of this project i’m working on, as I need to be able to move freely like this for example;

The mouse is supposed to control the character’s rotation, and it does just fine save for being locked on this axis. It is in a water physics volume, so it should be able to freely move up/down/left/right and so on. I’ve followed every tutorial there is and none of them seem to work.