abaqus warnings

Hi Dear all

I am mozaffar M.S.C Student in polymer engineering.I am modeling a multi layer of rubber and fiber. I have assigned the Mooney Rivlin hyperelastic model and elastic model to rubber layers and fiber layers respectively.and I have used a discrete Rigid on top of layers, and there are penalty interaction between  one rigid layer and first rubber layer and another fiber and rubber layers.and I have assigned reference point in part module and reference node in interaction module to rigid body. I have assigned a  uniform pressure load to top surface of rigid body and a displacement u2 to reference node. my step is dynamic implicit.

I have some warnings and my job is run until 99th increment and is aborted:

warnings:

1.Boundary conditions are specified on inactive dof of 57 nodes. The nodes have been identified in node set WarnNodeBCInactiveDof.

2.Solver problem. Zero pivot when processing D.O.F. 2 of 16 nodes. The nodes have been identified in node set WarnNodeSolvProbZeroPiv_2_1_1_1_5.

3.For contact pair (assembly_r1-st-assembly_st-r1), adjustment was specified but no node was indeed adjusted more than adjustment distance = 2.22000e-16.

Plz help me.

Best Regards

mozaffar.mokhtari@yahoo.com