12voip Forbidden msg

I been using the betamax voip services for some time. I started a new voip server copied the same settings and now getting the following error.
It registers fine with the voip provider

[May 29 13:32:37] WARNING[13491]: chan_sip.c:16060 handle_response_invite: Received response: “Forbidden” from ‘“asterisk” sip:username@sip.12voip.com;tag=as47d2098d’
– SIP/12voip-08a65bc8 is circuit-busy
== Everyone is busy/congested at this time (1:0/1/0)

below is my sip.conf file. It registers with no problem. I can use sip with the same settings directly from XLITE, my Nokia phone etc however with asterisk I am having a problem now.
Asterisk version 1.6xx
any input will be appreiciated
thanks

sip.conf file

[code][general]
;NAT STUFF
nat=yes
externhost=xxxx.xxx.xxxx
localnet=192.168.1.0/255.255.255.0
externrefresh=10

[default]
bindport = 5060
type = friend
disallow = all
allow = ulaw
allow = alaw
allow = gsm
secret = 1234
host = dynamic
qualify = yes
context = default
canreinvite = no
dtmfmode=rfc2833
call-limit = 2

12voip
fromdomain = sip.12voip.com
fromuser = username
host = sip.12voip.com
bindport = 5060
insecure = very
secret = password
type = peer
username = username
qualify = yes
context = outbound_allroutes[/code]