Help debug calling name

I have 2 phones with 2 DIDs and inbound routes. On inbound external calls Phone1 shows caller-id number and name and the other shows number and number. Internal calls show name on both.

There are identical in every respect I can see… Same firmware, same trunk, same settings on the extension and inbound routes. All the SIP messages look the same.

In the logs I see this:
Call to Phone 1
…“CALLERID(number)=5107785612”) in new stack.
…“CALLERID(name)=5107785612”) in new stack

Call to Phone 2
…“CALLERID(number)=5107785612”) in new stack
…“CALLERID(name)=MILLION CHRISTO”) in new stack

How can figure out why Asterisk treats these 2 phones different? Thanks.

You would need to show the actual SIP traffic and full console output and dialplan for each.