Two atons in a simulation

Hi

I'm trying to do a simulation with materials of different diameters (two materials). But I'm facing the following error:

"ERROR: Fix property/global (id m3): per-atomtype property matrix must be symmetric, i.e. N atom types require you to define N columns and N rows with N*N total values (../fix_property_global.cpp:158)"

In my settings are:

fix m3 all property/global coefficientRestitution peratomtypepair 2 0.8 0.8 0.8 0.8
fix m4 all property/global coefficientFriction peratomtypepair 2 0.15 0.15 0.15 0.15

How can I understand and solve this problem?

And taking advantage of the topic to ask a second question, is there any way I can perform mesh refinement on a geometry in the LIggghts settings?

Thanks