Error when running 04-random.game with Obfuscated JAR

[wsongah]

For the other 4 puzzles, they run ok with Obfuscated JAR, which means I successfully start the game. But when I enter "java --enable-preview -jar PA1-obf.jar ../puzzles/04-random.game", I got this:
Exception in thread "main" java.lang.IllegalArgumentException
at a.g.(Unknown Source)
at b.?.?(Unknown Source)
at b.?.?(Unknown Source)
at hk.ust.cse.comp3021.pa1.Main.main(Unknown Source)
Why? Does it mean there is something wrong with the main file?
Thank you!

[Derppening]

#35.

[wsongah]

Thanks!