Unlike the modern Creative Cloud subscription model, Adobe Acrobat Pro 2020 is a perpetual license —you buy it once and own it. However, that also means you have to manually unlock it using a 24-digit alphanumeric code.
If it still says “Trial Mode” , restart your computer and try entering the code again via . For persistent errors, Adobe’s chat support (free for perpetual license holders) can reset the activation count on your key. adobe acrobat pro 2020 enter serial number