Can you confirm if you can dial out by manually entering the phone number using your phones dial pad?
If so please let us know so that we can check you have your Click2Call settings set up correctly.
If the issue still persists, please check you do not have Do Not Disturb (DND) activated on your phone.
If the lines are still engaged please try re-booting your phone and router if necessary - disconnect all cables and after 5 minutes re-connect which should then bring your phone back online and you should then be able to make outgoing calls.
If there is still a problem after doing the above please contact our Support Helpdesk for assistance.