AR Core - UI messing up when walking into 3D model

Hi,

I'm recently started experimenting with AR to place real sized objects. In the last version I;m building my UI looks fine until I start to walk into the 3D model. Feels like there is a problem when the AR camera intersects with the spawned model. I'm running Unity 2018 with ARCore 1.2 and modified helloAR with a Samsung S10 to help me spawn only one instance of the 3D object. Here are some screenshots that I think it illustrates what's going on. I don't know if I'm missing something. Please advice.

Thanks,
Paul