Suddenly unable to continue?

[Assassine]

Until a couple of weeks ago, ive been regulary riddling here together with a friend. A few weeks ago, we stopped at minus 33.
I still had a tab in firefox open on the level in case we want to go on some time. I also made a .txt doc with all urls and passwords we had so far.
I just refreshed the tab with that level, thinking i could try it again, and got the following error:
<URL removed> :: God kills a kitten everytime you cheat. Stop killing kittens please. If you like send a mail to DavidM with subject 'minusnotpronrulez' and put this number in the mail: 22 10 2013, 13:39:34
Going back using the txt i had created, i got the same error on levels 32 and 31. Level 30 works, but i seem to be unable to go on from there suddenly.
Why is that and how can i fix it?

Edit: Spelling mistake

[frkyjenn]

Please do as it says and contact DavidM.