Sometimes AGs online save system works a a lil bit weird... mostly its only a small issue and all worked fine after again after a short time... sometimes even a simple site-refresh fix the problem.
I tested it yet and it workd fine for me, so try again.
Besides this: make sure your browser/flash is up to date. If the problem still persists on your side, you can try two other things:
1.) try it by using the privacy/incognito-mode of your browser 2.) try another browser and see if that change anything
You should see the message "Welcome, you have found the RESTful version of our AGI.". If you get any kind of security/certificate warnings, it may be that your browser thinks our cert is bad, and you will have to add services.armorgames.com to your accepted sites list in your browser, or refresh your browser cache.