If you are still unable to make a call, please refer to the following table for help with resolving the issue: Need help with making a call from Skype? Check out this guide on how to make a call in Skype. You can then call a number on your contact's profile or use the dial pad to enter a phone number. To make a call to a mobile or landline, you will need to have Skype Credit or a subscription.
If you experience trouble making a call in Skype, then it is always good to check for any current issues on the Skype Status page.