Yast not working after 13.1 upgrade

Was running 12.3 and upgraded to 13.1. Everything so far seems to be working fine (php/apache/mysql/dhcp) but I’ve run into a problem when running yast (I’m running text only version of OpenSuse)

I run yast and nothing happens - it returns to the command prompt. No errors, nothing in the error logs.

Any ideas how I can troubleshoot this?

Yast --help shows the help but if I run yast or yast module for example nothing happens.

Problem fixed. I eventually checked the y2log file and found the problem was caused by ruby2.

https://forums.opensuse.org/showthread.php/492723-After-installing-some-dependencies-yast-will-no-longer-launch

this was the command i had to use to fix it:

rvm use system --default