Caller ID Header

In the advanced settings, you can choose between two Caller ID headers. By default, this is set to FROM. When a call has been transferred, the internal extension number appears on your display instead of the original number of the caller (who has been transferred). The Remote Party ID Sip header option allows you to see the caller's number after the transfer. However, the device must support this feature, which is why this setting is set to FROM by default. Below is a list of devices that support this function.

After setting [Remote Party ID sip header] in the advanced settings, you can save the VoIP account.

Yealink

Under the [account] tab followed by [advanced], select RPID-FROM for [Caller ID Source]

Cisco

Go to the [voice] tab followed by [ext*]. Under [SIP settings], select YES for [SIP Remote-Party-ID]