Recently active topics in Dipity tagged with url

RSS feed won't add -- is it due to 'https' or something else:

URL is https://mysite.wsu.edu/personal/yeide...

How does dipity decide what my url is? I chose my first name as my user name. For example "name". I got that user name, but my url has my name plus the first letter of my last name. Like "name_L".

Why? Does that mean my first name was taken as a url? And if that's true, I'd rather have my full name as the url, not just a last initial. Seems like we could have the choice.