[Jan  6 10:23:39] ERROR[5758] pjsip:    sip_transport. Error processing 789 bytes packet from UDP 45.115.149.5:5060 : PJSIP syntax error exception when parsing '' hea
der on line 3 col 29:
INVITE sip:87640475343804107@22.73.22.39 SIP/2.0
Via: SIP/2.0/UDP 45.115.149.5:5060;branch=z9hG4bK01d3b09b6b21b00e
From: "اسماعيل" <sip:اسماعيل@45.115.149.5>;tag=6e1d71e43ae3ba8b
To: <sip:87640475343804107@22.73.22.39>
Call-ID: 043cf6ec0cae62d963616c6c0dc6dd2c@45.115.149.5
CSeq: 1 INVITE
Contact: <sip:اسماعيل@45.115.149.5:5060>
Allow: INVITE, ACK, CANCEL, BYE, OPTIONS, INFO, UPDATE, PRACK
Supported: timer
Max-Forwards: 70
User-Agent: SomeSwitch V2.1.2.4
Session-Expires: 600
Content-Length: 222
Content-Type: application/sdp

v=0
o=- 46616 46616 IN IP4 73.26.42.78
s=VOS3000
c=IN IP4 73.26.42.78
t=0 0
m=audio 6654 RTP/AVP 18 101
a=rtpmap:18 G729/8000
a=fmtp:18 annexb=no
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-15
a=sendrecv