Coulomb cutoffs of pair hybrid sub-styles do not match

Dear Users,

I am trying to simulate MgO bulk structure as a very first practice of LAMMPS.

I am using the tabulated Buckingham potential of MgO bulk.
—> If I use tabulated potential is it correct to use [ pair_style hybrid/overlay coul/long 15.0 table spline 20001]?

However, the calculation which operated from the input file (in below) results the error:

Could you please advice me which cutoff is suitable for this simulation ? And why?

You should use the same cutoff (12) as used by the table. Using a larger real space cutoff for coulomb usually comes with a performance penalty anyway.