Hi there!

Thanks for contacting us.

Did you updated the system plugin of helix to the latest? Actually the Revibe template doesn't get the compatibility update for the new Helix3 as well as Joomla 4. So if you have updated it, kindly get back to your last working version of the site from backup.

However, if you manually include the following custom code in your custom CSS:

#sp-header .row {
    display: flex;
}
#sp-menu {
    flex: auto;
}

It will serve your purpose anyway!

Note: Path towards custom CSS(Joomla 3): Extensions>Templates>Styles> Click on your current default template name then choose Template Options. Then find custom CSS within the custom code.

Best Regards