[Serusers] Communication Problem btw SER and User Agent

Hi, Here is an indication that my SER is running: micadeyeye@asmicom:/usr/src/Research-Progress$ ser Listening on udp: 127.0.0.1 [127.0.0.1]:5060 udp: 196.24.224.76 [196.24.224.76]:5060 tcp: 127.0.0.1 [127.0.0.1]:5060 tcp: 196.24.224.76 [196.24.224.76]:5060 Aliases: tcp: asmicom.local:5060 tcp: localhost:5060 udp: asmicom.local:5060 udp: localhost:5060 --------------------------------------------------------------------------------------------------- But each time I tried connecting to it from a USER AGENT (ZAP, UCTIMSCLIENT), it doesn't interact with the client. I checked my dump(via wireshack) but only REGISTER messages are sent with no reply from SER. Can anyone help me? I have both SER and client sitting on same PC (using same port-5060).