It may be that you can’t use your Skype Number as caller ID in your country. You can set up caller identification using your Skype Number in many countries, but there are still a number of countries where this is not yet possible. Click here to see if it’s currently available where you are.
If you are not able to use your Skype Number as caller identification, then you can use your mobile number instead.
Find out how to set up Caller identification using your mobile number.