Directed Pickup Caller ID

I am having some trouble with directed pickup using a Polycom 650. I can do directed pickup just fine however the caller ID information that shows up on the monitoring phone is not correct. I think the problem has to do with the SIP contact header, but I am not sure.

When a call comes in to the monitored phone the monitoring phone displays:
To: sip:2520@HostName
From: 2520 (2520)

The SIP message is:
NOTIFY sip:usi-0004F22AB878@IPAddress:5060 SIP/2.0
Via: SIP/2.0/UDP IPAddress:5060;branch=z9hG4bK56b671d5;rport
Max-Forwards: 70
From: sip:2520@HostName;tag=as10a354e7
To: “usi-0004F22AB878” sip:usi-0004F22AB878@HostName;tag=4A2EF907-722CC036
Contact: sip:2520@IPAddress
Call-ID: 65c2f5b4-160d510f-a5ffab1e@
CSeq: 107 NOTIFY
User-Agent: Asterisk PBX
Event: dialog
Content-Type: application/dialog-info+xml
Subscription-State: active
Content-Length: 525

Thanks in advance for your help. Also, let me know if you need any more information.