Yealink T5 Series User Manual page 151

Enter the directed call pickup code in the Directed Call Pickup Code field.
3.
Click Confirm.
4.
You can also configure the directed call pickup code on a per-line basis:
Procedure:
Click Account->Advanced.
1.
Select the desired account from the Account field.
2.
Enter the directed call pickup code in the Directed Call Pickup Code field.
3.
Click Confirm.
4.
Basic Call Features
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