Customize is not working??

I am using the Fashionistas theme for a while and I never had a problem. Recently I wanted to change my header, so I went to Customize (as always) and I find that every option in that bar is gone. There is no text, only ‘Save & Publish’ at the top. If I log on to another laptop there is the same problem. I deleted the theme and installed it again but that didn’t help. I also deleted my entire history on the laptop but no result either.

Does someone know what’s wrong? I am not working with codes and CSS and stuff. I can’t change my header or fonts and it’s very frustrating since I want to keep the theme..

My blog is http://www.fantestisch.nl

Thanks a lot!