Most of the customers meet this kind of problem: When you using call pickup to pickup the call, then on your IP phone's screen, you would just see the '*04' or '*4', but actually you need it shows the caller ID number after pickup. In this guide, we will teach you how to make it.
This guide has been tested with S-Series VoIP PBX firmware version 30.10.0.x or later and Yealink T28P firmware version 188.8.131.52.
1. Settings on S-Series VoIP PBX
Enable option "Send P Asserted Identify" on "Settings->PBX->General->SIP->Advanced", then apply changes. "Send Remote Party ID" is either fine.
2. Settings on Yealink IP phone
Setting Caller ID Source to "PAI-FROM" or "RPID-FROM"on "Account->Advanced->Caller ID Source"
It might have the similar settings for other brands of IP phone. You could refer and configure accordingly as per their use guide.