licensing not working

Hello Ladies and Getelman, I am a student of the TU-Wien in engenering. I really like the Cad lessons and have great fun creating parts and assemplys with Creo butrecently my licensestoped working. I tryed activating it again with the installation guide providet by the TU but every time i try to put in the licencing Code It just says Error (Fehler!). I asked my proffesors about this and they just sayed that it looks like they can´t do anything and i should figure out a allternative like working on the projekts from a friends PC. But a have a assiment due the 24. and every student got a differnet one so i would have to make everything again with took an entire semester with 4 weekly hours each and many more at home. I don´t know what i can do, maybe i am just to dumb to install a new license. I would really appriciate a repply with a solution to my problem if there is one. Thank you either way for listening to my problem. Thank you again- Matthias Eder