"Failed to compute elastoplastic strain variables" Help Please

Hello,

I am an absolute beginner at COMSOL Multiphysics and I am trying to model the effect of the movement of soil on a steel pipeline buried in it. I have attached the model file with this post. I am trying to use the Soil Plasticity Criterion but as the tutorial describes, It needs to be given Initial values. So following the built in tutorial, I have included two studies, one for calculating the initial stresses and the other one for calculating the actual stresses on the pipeline.

I would be really grateful if someone could take a look and point out the mistake in my method.

Thanks in advance.

- Rohit