Adobe Acrobat Pro DC

I purchased a one-off lifetime subscription to Adobe Acrobat Pro DC in 2016 and it allows me to put the program on 4 separate devices. When I log in to my Adobe account, I cannot see my product there in order to change the devices I have instaled the program on and when I called Adobe they say they do not support my product any more. I have installed the product on an old laptop that I no longer have, so I cannot physically uninstall it on that device. I want to puit in on my new laptop but when I try, I am told that the program is already on 4 separate devices. How can I now alter the device list for my product and free up 1 device so I can install it on my new laptop??