When configuring a user Outbound Caller ID, voice message saying the call is denied by the administrator

[overtech_nc]

Hi,

One of my customers asked me if it would be possible to let people know he's the one who's calling them when he uses 3CX.

There's only the main trunk number, no additional one to allocate to a user, so I asked the carrier if they allowed custom caller IDs. Here is their answer:

We use the "from" field to present the number to the called party. You are free to enter any value you like.

However, if the format is not suitable for the recipient, we will replace it with the PAI (if you present a name for a call to a landline or mobile, the PAI will be used, if it is sent to an IPBX behind a SIP Trunk, the name can be transmitted).

It is recommended that you present the DID in international format (e.g. +687413560), or the original caller's number if the call is transferred.

Is there a specific field that allows us to change the value of this "From" field on a "per user" basis?

The only thing that comes close to this for me is the "Outbound Caller ID" field in the users section, but when I tried inputing the mobile number of the user (in international format), they were told the call was denied by the administrator...

Is there any way to present a different number than the main trunk number for users that would need it?

Thanks!