Unable to understand this error

Hi all,
I am new to Comsol and I am trying to give a 3D laminar flow(spf) with time dependent studies in a cluster. I am using Comsol 5.2 and I am getting the following error.

Current Progress: 0 % - Form Union
Memory: 492/492 2020/2020
Open time: 43 s.
Running: Batch 1
Current Progress: 0 % - Reference 1
Memory: 474/492 2016/2020
Current Progress: 0 % - Free Tetrahedral 1
Number of vertex elements: 0
Current Progress: 0 % - Creating boundary mesh
Memory: 475/492 2092/2092
Current Progress: 0 % - Boundary Layers 1
Memory: 475/492 2096/2096
Current Progress: 0 % - Smoothing transition to interior mesh
Memory: 476/492 2096/2096

/******************/
/*****Error********/
/******************/
The following feature has encountered a problem:
Problem setting up multigrid.
Unsupported geometric entity level.
Error in multiphysics compilation.


I have tried both Domain decomposition and Multigrid method for the Iterative methods and both methods are giving the same error. Any help would be really appreciated. Thanks in advance.