There are many things you can do.
1.Call Autodesk by email and demand a new activation key.
2.Activate in offline mode and send them the code and they will send you a response code.
3.(optional)Sue the company if they don't want to help you for the product they took your money?..
4.If you are from Europe, the Directive of the European Parliament and of the Council on the legal protection of computer programs:
https://eur-lex.europa.eu/legal-content/en/TXT/?uri=CELEX:32009L0024
Point 13 clearly says that you can open the software by your own means if the company doesn't provide support.Mainly this line:
''This means that the acts of loading and running necessary for the use of a copy of a program which has been lawfully acquired, and the act of correction of its errors, may not be prohibited by contract.''
So in the European Union, the contract that AD tries to restrict the costumer does not apply as it was voted already in 2009.Ten years before the new invented rules by Autodesk.
5.This is additional option(included for the fanboys that may come), but move to subscription and loose the current software.
Good luck.
