If you want to change the name of your developer account that is displayed in the app stores, then you can do the following.

For the Apple App Store, you will need to contact them directly. It concerns a personal account and we can't do it for you.

https://developer.apple.com/contact/phone.php

If you want to change your name in the Google Play Store: 

1. Login to your account at https://play.google.com/apps/publish.
2. Go to Settings.
3. Change your developer name.