You should go to your learner home section then look under "edit profile" button.

I have a problem like that. I can't find any mastered.

Hi nairavanthika19, 

You can find your energy points below the "Edit profile" button in the Learner Home:

Hope this helps!

Hello, I have 50,000 energy points but it is not unlocking any skins, I even tried refreshing the tab but nothing happened, please help me out.

Thank you

Same bro

Hi everyone!

We'd love to have a greater understanding of the issue you're running into. Could you please submit a support request in our Help Center? Here's the link: http://khan.co/KA-support. 

Thank you for being a part of Khan Academy!