Hello. My name is***** can help you with your question.
If there is something you normally have to dial to get an outside line, make sure you are including that in the phone number that you are entering as the destination phone number. Sometimes this will all automatically be added using the dial plan but if you're getting a fast busy signal, that would normally indicate that you are not accessing outside line at all. Adding the access code should correct the issue. If it does not, or if you still questions, please let me know.