I need to change order of items inside one category in the portfolio.
If I modify PROJECT OPTIONS, option Portfolio order by I change the select option, but always I get the same order.
Please make sure that you are using the latest versions of the theme and the recommended plugins. Then clear cache and check back.
If the problem still occurs then deactivate all the third party plugins and provide with the admin panel login details of the website then we will troubleshoot with the theme plugins.