My Presence module works fine with PUBLISH request, but not with SUBSCRIBE request. The trace shows as follows, the requestURI is the IP address of Presence module, and the request directly sends to presence server, I think there must be something wrong with the structure of SUBSCRIBE request. any one can point what is wrong will be helpful , Thank you!

---------------Sending Request---------------
PUBLISH sip:148.88.233.209:5065 SIP/2.0
Call-ID: ef68e3acb55c2a4c791b1e31f7362b6f@148.88.232.101
CSeq: 849 PUBLISH
From: <sip:alice@148.88.232.101:5061>
To: <sip:alice@148.88.232.101:5061>
Via: SIP/2.0/UDP 148.88.232.101:5061;branch=z9hG4bK19953
Max-Forwards: 70
Expires: 3600
Event:  presence
Contact: <sip:alice@148.88.232.101:5061>
Content-Type: application/cpim-pidf+xml
Content-Length: 220

<?xml version="1.0" encoding="UTF-8" standalone="no"?><presence xmlns="urn:ietf:params:xml:ns:pidf" entity="pres:alice@open-ims.test"><tuple id="sip-client(java)"><status><basic>online</basic></status></tuple></presence>

---------------Received Response---------------
SIP/2.0 200 OK
Call-ID: ef68e3acb55c2a4c791b1e31f7362b6f@148.88.232.101
CSeq: 849 PUBLISH
From: <sip:alice@148.88.232.101:5061>
To: <sip:alice@148.88.232.101:5061>;tag=762c87025812f63000552d0e54932ab8.31c6
Via: SIP/2.0/UDP 148.88.232.101:5061;branch=z9hg4bk19953
Expires: 3590
SIP-ETag: a.1184861600.3810.10
Server: OpenSER (1.2.0-notls (i386/linux))
Content-Length: 0


---------------Sending Request---------------
SUBSCRIBE sip:148.88.233.209:5065 SIP/2.0
Call-ID: 5c280b2299c2834b7705dece8497ec2f@148.88.232.101
CSeq: 20 SUBSCRIBE
From: <sip:alice@148.88.232.101>
To: <sip:bob@148.88.232.101>
Via: SIP/2.0/UDP 148.88.232.101:5061;branch=z9hG4bK97556
Max-Forwards: 70
Expires: 3600
Event:  presence
Contact: <sip:alice@148.88.232.101:5061>
Content-Length: 0

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