New Collision Channel Grayed out

I’m not sure what happened here, but I can no longer create new Object or Trace Channels. They just went grey all the sudden. Anyone know how I can get fix this? Thanks.

“You can have up to 18 custom channels including object and trace channels”

I thought it was 18 channels for objects AND! 18 channels for traces. It’s 18 combined. I just used all 18 so the buttons went grey :expressionless: