Error in using EAM, AIREBO, LJ in one simulation

Good day lammps-users!

I am from the Philippines and new to lammps. May I ask, how can I deal with the error I’m facing now regarding interactions between Carbon and Copper? I want to investigate the growth of graphene on copper by depositing carbon on top of copper surface. I am using eam, LJ, and airebo potentials.

ERROR: Not all per-type masses are set

This is my code for this.Can you help me debug the program?
How can I write this in proper way so that the program will work? Thank you in advance.

pair_style hybrid eam/fs lj/cut 2.5 airebo 3.0

pair_coeff * * eam/fs Cu.eam.fs Cu NULL
pair_coeff * * airebo CH.airebo NULL C
pair_coeff 1 2 lj/cut 0.001 3.274

The error is pretty self-explanatory - you haven’t set masses for all atom types: http://lammps.sandia.gov/doc/mass.html

Michal