Realize that Skype is run by Microsoft, so it will likely use your password for your Microsoft Log In. If you changed if for another application (like XBOX, MS Office products, etc) then try logging in with that password first.
If no luck, try the following:
1. go to
https://www.skype.com
2. on upper right select sign in
3. in the drop-down menu select "Use Skype Online"
4. on the sign-in page, enter your email
5. on the "Enter Password" page, go to the bottom and select "Forgot My Password"
6. the next page will ask, "Why can't you sign in?" Select I forgot my password
7.On the "Recover your account" page enter your email and the letters for the CAPTCHA displayed.
8. On the "Verify your identity" page, enter the code from your app, or select the link at the bottom of the page that says, "
Use a different verification option". If you select the link it will then ask for your email, and then hit the "Send Code" button.
9. Check your email for the code, and then enter it
10. It will bring you to the "Reset your password" page where you can enter your new password.
Good luck!