I am making a Coupled Eulerian-Lagrange model. Here I have two layered soil. So I wish to assign a volume fraction but cannot give that. An error(screenshot attached) "The selected part instance has multiple section assignments. Eulerian parts should have one section assignment only. Remote Extra assignments". But I have two layers of soil; how to do that?? I have done partitions to my model to make proper meshing. But in error, it is forcing me to make one section only. How should I resolve the problem?

Abaqus ​​​​​​​