So I have some workers who need to call clients from outside the office. Their phone plan allows them to have free calls to a certain provider, while others cost almost 30c per minute, which would end up being really expensive. In the office, we have VoIP providers which cost us less than 2c per minute. What I have done is bought an extra sim card for the same carrier as the techs with unlimited incoming minutes as well as a GSM gateway which I have connected to 3CX. (This is OK with provider, I asked) I want the techs to be able to dial the number of that SIM in the gateway for free and then from there be able to call the clients through the office cheap line. The digital receptionist only allows the caller to dial internal extensions, and nothing that applies to outgoing rules, so if I call the receptionist and try to dial a number which matches an outgoing rule it replays the message. So how can I set this up? The techs don't have mobile data, so they can't use the internet.