We are extremely sorry for issue caused by our font converter server downtime. We had overload in our server and it failed. We have moved to another server now and hope there won’t be any problem. We will do monitor it for few days.
Also, please be clear that it only affects new font upload process. The font already uploaded and used in your site will work as those are served from your own location. Our server just converts the font and sends back font file to store in your server.