Problem with dHCP Surface Template

[MahShidF]

Dear Expert,

I wanna display some nodes on the dHCP surface template provided in :
https://biomedic.doc.ic.ac.uk/brain-development/downloads/dhcp-neonatal-surface/
Actually, by merging both the right and the left hemisphere, they did not stand aside each other and form a complete brain. They have far distances from each other. Now, I am wonder if they are in the same space? Also, I attached an image, showing the merged hemispheres.
I would apprecaite if you could help me to put them aside each other.

Regards,
Mahshid