Outbound calls not working

I configured sonetel, asterisk and X-lite. When incoming calls are made to sonetel number, it is routed to asterisk. X-lite rings and everything is ok.

But, when I make an outgoing call from X-lite, I get the below errors in asterisk console.

asterisk*CLI> == Using SIP RTP CoS mark 5 -- Executing [00XXXXXXXXXXX@mercuryh:1] Answer("SIP/7002-00000012", "") in new stack -- Executing [00XXXXXXXXXXX@mercuryh:2] Set("SIP/7002-00000012", "CALLERID(num)=paul") in new stack -- Executing [00XXXXXXXXXXX@mercuryh:3] Dial("SIP/7002-00000012", "SIP/00XXXXXXXXXXX@paul") in new stack == Using SIP RTP CoS mark 5 -- Called SIP/00XXXXXXXXXXX@paul [Nov 26 23:05:51] WARNING[11755]: chan_sip.c:20245 handle_response_invite: Received response: "Forbidden" from '"Hernan" <sip:paul@>;tag=as292ce80b' == Everyone is busy/congested at this time (1:0/1/0) -- Executing [00XXXXXXXXXXX@mercuryh:4] Hangup("SIP/7002-00000012", "") in new stack == Spawn extension (mercuryh, 00XXXXXXXXXXX, 4) exited non-zero on 'SIP/7002-00000012' asterisk*CLI>

Any idea about this issue? What might be going wrong? Please help.

Nevermind, it was again a configuration issue. I fixed it.