Mathcad 3.1 perpetual license cant be activated anymore

In 2016 I bought a perpetual license for Mathcad Prime 3.1 through my schools discount program. When trying to activate the product code now i get errors saying that the program ID has already expired. Both through the software itself and the web portal described here:

https://community.ptc.com/t5/Mathcad-Tips/Transferring-Mathcad-Single-User-or-Student-license-from-an/ta-p/819143#M1600

Being a perpetual license it shouldnt expire, any help to get this activated on my PC would be appreciated