403 Forbidden

I have SSIpura SPA1001 and I tried to configure it with one of the VOIP
providers. Evrytime I dila I receive busy signal. I thought it is dial
plan issue but after checking the log it looks like there is another
issue and I have no clue what Im doing wrong.
Below is part of log that I think is important.
ANYONE can help please?


SIP/2.0 200 OK
[0]Off Hook
Calling: />
[0:0]AUD ALLOC CALL (port=16430)
[0:0]RTP Rx Up
RSE_DEBUG: reference domain:sip.tlenofon.pl
INVITE sip: SIP/2.0
CSeq: 101 INVITE
CSeq: 101 ACK
CSeq: 102 INVITE
Proxy-Authorization: Digest
username="MyID",realm="sip.tlenofon.pl",nonce="6dd 2e523
href="private.php?do=newpm&u=">022XXXXXX />
SIP/2.0 403 Forbidden
CSeq: 102 INVITE
CSeq: 102 ACK
[0:0]AUD Rel Call
CC:Failed
[0]On Hook

AP