T21P dial problem

[oguzhan]

Hello,
I am running asterisk with Yealink phones in company..
Only two of the phones has a strange problem.
There is two subscriber.. 320 and 224..
320 can call everybody except 224.
224 can call everybody..and also be called by everybody except 320.

Both phones has same fw and hw versions.
Yealink SIP-T21P 34.72.0.75
HW: 34.1.0.0.0.0.0

Factory default both phones.
No DND or call block configurations
Asterisk has no additional rules or configs except direct dial.

When i call from 320 to 224.. all i can see on asterisk is;


Executing [224@from-internal:8] Dial("SIP/320-0000c90f", "SIP/224,15,tTkK") in new stack
== Using SIP RTP CoS mark 5
== Extension Changed 224[BLF_GROUP] new state Ringing for Notify User 444
-- Called SIP/224
== Extension Changed 224[BLF_GROUP] new state Idle for Notify User 444 (queued)
== Everyone is busy/congested at this time (1:0/0/1)

Phone has multiple call so, cant be busy..
Also changed the DND and Blacklist return messages to 404, to see if it stucks on such rule or not..
Still no solution.
Something strange happening here and I cant figure out what is it.
Probably a bug..