Unless it has changed recently, Skype Connect didn't/doesn't allow you to "call" a Skype name. It's considered a "business" service. You required the "old/basic" Skype service, and with 3CX, that meant using the, now obsolete, 3CX Skype Gateway. This involved having the PC you were using 3CX on, running a valid/registered Skype account. 3CX was never able to send calls to a Skype contact without you first setting up your own Skype account.