If calls forwarded by 3CX show up on the remote phone as Anonymous, ensure the following settings are configured on the VOIP Provider Outbound Parameters tab.
From: Display Name - "OriginatorCallerID" Original Caller number will be sent
From: User Part - "OriginatorCallerID" Original Caller number will be sent
Remote Party ID - Calling Party: Display Name - "OriginatorCallerID" Original Caller number will be sent
Remote Party ID - Calling Party: User Part - "OriginatorCallerID" Original Caller number will be sent
