Minecraft Preview Deferred Technical Preview not working.

Whenever I tried to enable Deferred Technical Preview, it does not allow me to. If you look here:

 

It's not enabled for me to use. I tried using a resource pack, not using a resource pack, and I've tried using multiple of them. Additionally, I am on DX12 as listed here:

However, it is not reporting this. Please help me enable Deferred Lighting for the Minecraft Preview version. Here is the debug text it lists above:

Thank you all and have an amazing day!