Camera following the player

Hm, hard to say without knowing your used camera control - are you using one of ORK's built-in camera systems or a custom one?

For custom controls, check out the documentation on player/camera controls.
Generally, you'd need to register it with ORK/Makinom to be able to block/unblock the camera control when the game should do that. In case some special setup is needed, you can use wrapper components, the documentation has some examples for Cinemachine and OOTII.

For built-in controls, make sure your player is spawned by ORK (e.g. via the start game schematic and scene changers). If you have some player already placed in your game scene that ORK knows nothing about, it's not recognized as the player's game object.

I've also found the same thing happens when changing the scene. It doesn't automatically connect to the character, there's also a big black box that appears on the screen when changing scene.
Im not sure if they're connected issues, but we're having a collaboration to troubleshoot soon so any insight would be quite helpful.

If you're changing the camera target during battle (e.g. via the Battles > Battle Camera settings, or as part of your battle animation schematics), make sure to return control to the player.
E.g. add a Camera Control Target node to your battle end schematic to reset target back to the player - the wrapper component should handle setting Cinemachine's target. Make sure camera controls are unblocked at that time, though :)