IE3D 2 port simulation (Help Jian)

Hi Jian,
To start with I am simulating pifa antenna using ie3d, extension for mmic scheme. and the design was working perfectly too..
In pifa I am using finite ground plane, so differential feeding I am providing to the structure having 1 mm distance from (finite) ground plane..

THe problem is coming when I am trying to place another antenna in parallel with the previous antenna on the same ground plane at some distance (i.e. 2 antennas on the same ground plane), and feeding it the same as single antenna
Error is coming "strucutre overlap at all global ports i.e. +1, -1 , +2 , -2 ports..
I am unable to understand why this error, may be I need some different kind of feeding?
because same design works in cst microwave studio setup.. Please help Jian..

Added after 2 minutes:

Thanks & Regards,
Nipun

You don't have room for the extension ports. You should try to use v-localized or h-localized ports.

Thanks Jian, i hope that will work