Project Settings> Default RHI stuck on DirectX 11, can't set to DirectX 12

Confusing issue. Quick google search turns up nothing.
In 4.27 when I try to enable Ray Tracing by switching Default RHI tp DirectX 12 and restart UE, sometimes it works but just as many times I stay stuck on DirectX 11 with no Ray Tracing.

Can anyone suggest why this may be happening?

if you go to your confg folder and in DefaultEngine.ini file edit the line

DefaultGraphicsRHI=DefaultGraphicsRHI_DX11  //put DefaultGraphicsRHI_DX12 here and save it

make that like so and it should load up in DX12.