Why can't i access dingleberry?

I'm currently trying to jailbreak my blackberry playbook. However, when i try to access dingleberry.it nothing happens, it just says "this site cannot be reached".

Why is this happening? Is there a way around it or another way to jailbreak my playbook to be able to install android apps?

That app and everything about it has been dead for years. It's not even relevant anymore. And your PlayBook can install Android apps without jailbreaking. Whether or not they'll run, that's a different story but the function is there natively.