Complaint

I have been sending numerous emails at UNISA regarding my certificate which I completed in 2018, they delivered it after I complained about the service we are getting at UNISA but guess what they delivered a certificate that doesn't belong to me, I tried to call them but no one ever bothers to answer the phones, I sent thousands of emails explaining to them that they delivered someone else's certificate I called the number which is on the envelope and its Ken's office number it will ring then goes to voicemail, I have sent emails to supervisors but I am literally ignored every day, and I Need the certificate at my workplace. UNISA doesn't value its students it's so sad.