DTMF does not show up in flow sequence

edit

I see the DTMF in the actual packet but when I go to Telephony then SIP Flows , Flow Sequence Typically the RTP (Telephone-event) DTMF would show.

It only shows the RTP DTMF information for some of the calls but not all of them.

WHy does it not show up properly on the flow sequence page?

wireshark version 3.6.0