Reason why Skype not responding:

• Check that your device has a stable internet connection with sufficient bandwidth.
• Make sure you're using the most recent version of Skype.
• Check to see whether your security software or firewall settings are obstructing Skype.
• steps to fix it:
• repair Go to Settings > Apps>on the left pane, select Apps & Features. Scroll down to Skype > Advanced options in the right-hand pane.
• Scroll down to the Repair button on the following screen. Check to see if Skype is now operating on your computer by restarting it.
• You can Reset Skype App if the repair option did not work. This essentially uninstalls and reinstalls Skype on your PC.
• Go to Settings > Apps > on the left pane, select Apps & Features. Scroll down to Skype > Advanced options in the right-hand pane.
• . On the following screen, press the Reset button.
• To confirm, click Reset on the confirmation pop-up.

Read More: What is Skype and how do you access and use it?