PSTN call transfer fails if agent anonymity is enabled in Skype for Business Server

Applies to: Skype for Business Server 2015Skype for Business Server 2019

Symptoms


When agent anonymity is enabled on the workflow in a response group in Microsoft Skype for Business Server 2019 or Skype for Business Server 2015, the agent is unable to transfer an incoming PSTN call to another PSTN user.

Cause


This issue occurs because the transfer request to PSTN gateway doesn't have any telephone number in the DID range. Thus PSTN carrier blocks the outgoing call.

Resolution


To fix this issue, install one of the following updates: