Invalide activationcode

Hello, I have installed SW2023 with an education serialnumber from my univerity. When I want to activate the licence it tells me that the licence is invalide. The total number of activations isn't reached and there is no other licence activated or saved anywhere on my laptop. The licence my university has is valid till the 31.7.2024.

Is there any way to solve this problem so I can use the program on may pc so I can finish my master thesis?

Thanks for your help.