Incorrect args for pair coefficients (../pair_reax.cpp:522)

Hi everyone,

I am trying to run the example “in.reax.rdx” in REAX folder. However, I got the error:
Incorrect args for pair coefficients. The version of lammps is 09-Dec/2014. Could anyone give some suggestion on this problem?

Thank you in advance.

Bests,
Shuai