Upgrade to 5.9.1 fails

It seems that the latest 5.9.1 has the fix for this issue with internal.GlobalVariable issue based on release notes. I tried upgrading my version from 5.8.0 to 5.9.1 on OS : MacOS High Sierra 10.13.6 but Upgrade failed with below error

Unable to download update file from Katalon server

java.io.FileNotFoundException: http://s3.amazonaws.com/katalon/update/5.9.1/macosx-x86_64/contents.tar.gz