This morning I got noticed that the US mirror server is down. NextArray's website is also down, so there is not much we can do.
In the meantime, you can change your package repository for France, Canada, or South Africa.
In /etc/pkg/GhostBSD.conf, change the URL of this line with the mirror URL you want:
Here is the list of mirrors:
I will make an announcement when everything is back in order.
Sorry for the inconvenient