how can i change the link name for my form

What do you mean? You mean the Custom URL as outlined in this guide: http://www.jotform.com/help/261-How-to-create-a-Custom-URL-of-a-form? 

If you mean your username (FritzLangFoundation), you cannot edit that. The only way to change that is to change your username to your preferred one. We can do it for you. Just please let us know the new username.