Cisco 7960 Incoming Call Problem

Hi All! I'm fairly new to FreePBX and am using this is purely a learning experiment.

I'm using a trial of SIPStation and when using a pjsip softphone I'm able to make and receive calls without issue (woo)!

The problem comes when trying to use my hardware Cisco 7960 phone. It can make outgoing calls as well as call my desktop softphone extension without issue. That works great.

It cannot receive incoming calls, either from my desktop extension softphone or from the outside.

When I fire up the asterisk console this is what I see:

localhost*CLI> pjsip show endpoints

 Endpoint:  <Endpoint/CID.....................................>  <State.....>  <Channels.>
    I/OAuth:  <AuthId/UserName...........................................................>
        Aor:  <Aor............................................>  <MaxContact>
      Contact:  <Aor/ContactUri...............................>  <Status....>  <RTT(ms)..>
  Transport:  <TransportId........>  <Type>  <cos>  <tos>  <BindAddress..................>
   Identify:  <Identify/Endpoint.........................................................>
        Match:  <ip/cidr.........................>
    Channel:  <ChannelId......................................>  <State.....>  <Time(sec)>
        Exten: <DialedExten...........>  CLCID: <ConnectedLineCID.......>
 =========================================================================================

 Endpoint:  100/100                                              Unavailable   0 of inf
     InAuth:  100-auth/100
        Aor:  100                                                1
      Contact:  100/sip:100@10.7.7.30:50019;user=phone           Unavail             0.000

 Endpoint:  101/101                                              Not in use    0 of inf
     InAuth:  101-auth/101
        Aor:  101                                                1
      Contact:  101/sip:101@10.7.5.40:39782;rinstance=271ac0d59  Avail               2.767

As you can see, 101 (desktop softphone) is available, while hardware Cisco 7960 (endpoint 100) is Unavailable.

This phone originally was giving me a 401 Unauthorized error when registering, which I fixed by setting force_rport=no inside of the pjsip.endpoint.conf, so it seems to register now and can place outgoing calls. But incoming is still not working.

I don't see anything obvious in the logs that would indicate why it's not working so I'm at a bit of a loss here. I did use the Open Source Endpoint Manager software to generate the configs for this device.

Any guesses as to what would help fix this are greatly appreciated. I've spent 2 full days googling before asking any questions, but I keep hitting dead ends.

Thanks!