i use 9.1.1 but has no problem at all
See the troubleshooting section of the documentation: https://docs.mendix.com/appstore/modules/data-grid-2#10-troubleshooting
Most likely, you are missing the `theme.compiled.css` in your `cssFiles` :)
Ive removed and redownloaded it and it is still showing vertical in design mode or while running. in structure mode it is showing the correct way. any idea what can cause this issue?
Thank you so much Fabian!! that fixed the issue. Read the whole documentation, except for that part, my bad.
Have a nice weekend!