Some calls in the asteriskcdrdb.cdr are classified as ANSWERED

[idan.ih2 (Idan)]

FreePBX version: 16.0.40.8
Asterisk version: 18.20.1

Hello,

I have an issue where even though there is no 200 SIP response (SIP response is 480),

the record in the CDR is ANSWERED, here are the records from the asteriskcdrdb.cdr for such call:

MariaDB [asteriskcdrdb]> select * from cdr where uniqueid = '1755910507.280' \G
*************************** 1. row ***************************
       calldate: 2025-08-23 00:55:07
           clid: "" <XXX>
            src: XXX
            dst: XXX
       dcontext: from-internal
        channel: PJSIP/3639-00000118
     dstchannel: PJSIP/OUT-Kamailio-00000119
        lastapp: Dial
       lastdata: PJSIP/XXX@OUT-Kamailio,300,M(post-outbound)b(handler^addheader^1)
       duration: 3
        billsec: 0
    disposition: NO ANSWER
       amaflags: 3
    accountcode: NULL
       uniqueid: 1755910507.280
      userfield: NULL
  recordingfile: NULL
           cnum: 3639
           cnam: XXX
  outbound_cnum: XXX
  outbound_cnam: NULL
       dst_cnam: NULL
            did: NULL
       CallerID: XXX
     HangupDate: NULL
     AnswerDate: NULL
queue_starttime: NULL
   DialedNumber: XXX
      queue_uid: NULL
        did_uid: NULL
        out_uid: NULL
          month: 0
         is_aws: 0
  recording_aws: NULL
         cdr_id: 3476
   queue_number: NULL
  last_dcontext: NULL
     hangupside: NULL
       linkedid: 1755910507.280
    peeraccount:
       sequence: 293
*************************** 2. row ***************************
       calldate: 2025-08-23 00:55:10
           clid: "" <XXX>
            src: XXX
            dst: XXX
       dcontext: from-internal
        channel: PJSIP/3639-00000118
     dstchannel: NULL
        lastapp: Congestion
       lastdata: 20
       duration: 2
        billsec: 2
    disposition: ANSWERED
       amaflags: 3
    accountcode: NULL
       uniqueid: 1755910507.280
      userfield: NULL
  recordingfile: NULL
           cnum: 3639
           cnam: XXX
  outbound_cnum: XXX
  outbound_cnam: NULL
       dst_cnam: NULL
            did: NULL
       CallerID: XXX
     HangupDate: 2025-08-23 00:55:13
     AnswerDate: NULL
queue_starttime: NULL
   DialedNumber: XXX
      queue_uid: NULL
        did_uid: NULL
        out_uid: 3639_XXX_1755910507560_56
          month: 8
         is_aws: 0
  recording_aws: NULL
         cdr_id: 3477
   queue_number: NULL
  last_dcontext: NULL
     hangupside: CALLEE
       linkedid: 1755910507.280
    peeraccount:
       sequence: 295

Log for such call can be found in my Dropbox:

C-00000094

Note: The ANSWERED dispo happens only for some of the calls and not all for all of them.

Will appreciate if you could tell me why it happens and how to prevent it.

Thank you!