When there's something wrong happened with your WordPress site, don't panic. In many cases, the cause of issues can be found and solved easily. Please try the following troubleshooting steps:
- First, make sure that everything is up-to-date on your site (WordPress, themes, and plugins).
- If you still have issues, try to switch the theme to the default WordPress' Twenty [xxx] theme (for example, Twenty Seventeen) to make sure that the issues you are having are related to the UXBARN theme you are using. If the issues are still there after switching themes, it means the issues are not from the theme, but they might be from any of the plugins you are using.
- Now you can try to disable the plugins one by one to see if any of them are the cause. If you find ones, please contact the plugin developers.
- If the problem occurred after you had customized the theme, try to revert everything back to the default state. This should solve the problem in most of the cases. After that, double check your custom code again before adding it back piece by piece.
The above steps are probably enough for troubleshooting the issues by yourself.
But if you see an error message like "500 Internal Server Error", it means there's something wrong on your server. Please contact your system admin to help you check the server's error log and to solve the issue.