call forward issue

[expack]

We have one AVAYA 9620 phone with 3 call-appr. This phone is receiving the forwarded calls from CISCO PBX.
Challenge here is : We are not getting forwarded calls on 2nd & 3rd call-appr. Callers are getting BUSY TONE.

Can anyone help to solve this. Is there any settings to be done at AVAYA side ?

Thanks for your perusal/help in advance.

 

[Midstream]

Does this station have a unique cover path?

Or, it may be that the Cisco system is misinterpreting the ACTIVE status of the Avaya phone to mean BUSY. Have you posted in the Cisco forum as well?

Have you tried tracing the Avaya station when it's active and a call is placed to it?