Transferring Microsoft Office Home & Student 2013 to a new device

Hi. I currently have Microsoft Office Home and Student 2013 Retail installed and activated on my old computer, which I am replacing with a new one.

I still have the original installation disc and the genuine 25-character product key. I purchased Office 2013 through official channels.

I have successfully installed Office 2013 on my new computer using the original installation media. However, when I try to activate it over the Internet, I receive a message saying that the product key has already been activated the maximum number of times permitted.

I then tried the telephone activation option, but Office displays: “Telephone activation is no longer supported for your product.” I also tried the telephone activation number listed for Mauritius, but the number does not work.

I only want to transfer my existing Office 2013 Retail licence from my old computer to my new computer, not use the licence on two computers simultaneously.

Could someone please advise me on how I can activate Office 2013 on the new computer?

Thank you.