explanations: We asked the university to issue a enrollment certificate, and now the Issuer is going to issue the certificate, and let's say the university has given us permission to do Selective Disclosure for ['name', 'studentId', 'department'].

explanations: When you run the issue function, the VC is issued, but why does the token keep changing every time you press the issue button? It's because we internally add a salt value and run a hash function to generate a new value for each issuance.