Different patches for fvPatchField

[Lianxiali]

It works if enableBalancing is false, but when it is true, I get the following error ( 2 processors with 2D problem):

[1] --> FOAM FATAL ERROR: (openfoam-2306)
[1] Different patches for fvPatchField
[1] 
[1]     From void Foam::fvPatchFieldBase::checkPatch(const Foam::fvPatchFieldBase&) const
[1]     in file fields/fvPatchFields/fvPatchField/fvPatchFieldBase.C at line 123.
[1] 
FOAM parallel run aborting

Can anyone know why or how to fix this problem?