VERY BAD NEWS! internal error in subroutine IBZKPT

[chemofish]

I encountered EIGHT continuous error messages before the calculation started:

VERY BAD NEWS! internal error in subroutine IBZKPT:
Reciprocal lattice and k-lattice belong to different class of lattices. 96

However, the calculation reached required accuracy and structural energy minimisation is successfully stopped. IS the result still reliable?

I used INCAR file as follow:
ISTART=0
ICHARG=2
PREC=High
EDIFF=1E-6
EDIFFG=1E-5
NSW=400
IBRION=2
NELMIN=8
ISYM=0
ISIF=3
ISMEAR=0
ISPIN=2
LREAL=Auto
LWAVE=.FALSE.
LORBIT=11

Could any expert tell me the underlying reason for this warning?