That's not a very descriptive assessment of the problem. "Can't open the disc"....there can be 100 reasons for that. Without knowing exactly what error you're getting, it's impossible to say.
Sorry was just reading the message it gave me:
Using LibreDrive mode (v06.3 id=64754CF46FCA)
Using direct disc access mode
Loaded content hash table, will verify integrity of M2TS files.
Downloading latest HK to C:\Users\student/.MakeMKV ...
Saved AACS dump file as C:\Users\student/.MakeMKV/MKB20_v77_PREY_332E.tgz
The volume key is unknown for this disc - video can't be decrypted
DEBUG: Code 0 at fQ@i{TOZMp! /b%`:121264372
DEBUG: Code 0 at fQ@i{TOZMp! /b%`:213131341
Failed to open disc
The ahem "key" in that message is the volume key unknown part. That should clue you in to look at the filename and compare it to the ones that have already been posted as not working.
Using LibreDrive mode (v06.3 id=4FBA32AEC678)
Using direct disc access mode
Loaded content hash table, will verify integrity of M2TS files.
Saved AACS dump file as C:/Users/Michael Cloude/Desktop/MakeMKV Output/MKB20_v77_PREY_332E.tgz
The volume key is unknown for this disc - video can't be decrypted
Failed to open disc