Click the Unblock button next to the person’s name.
If you're still having trouble, try signing out of Skype completely, restarting your device, and signing back in before repeating the steps above. how to unblock on skype
Unblocking someone on Skype is a straightforward process whether you are using a computer, a mobile device, or a web browser. Once unblocked, the person can see your online status and send you messages again. How to Unblock on Skype (Desktop and Web) Click the Unblock button next to the person’s name