2 columns is not working

The 2 columns set in categories is not working anymore.

Is this a conflict with the latest version of wordpress??

Please let me know how to fix it since having a 2- column list is pretty neat and clean for visitors.

I also noticed that the developer of this plugin is not active.

Is there a wayhow to contact her?

Thanks

https://www.ads-software.com/plugins/easy-restaurant-menu-manager/