Non-zero electric field at the center of disc

Dear All

I am doing electrostatic simulation using the 2D electrostatic module. In my geometry I have two discs forming core-shell structure. Then I inserted remanenet dielectric field displacement into the core and calculate the electric field. I was expecting the electric field at the center of the core-shell system will be zero in both X and Y components of the electric field (es.Ex and es.Ey) but I am getting non zero values in the Y direction.

I tried by changing the values of the remanenet dielectric field displacement but the result is the same. I have attached the line scan results.


Thank you