Please post a Real URL for "tag/capital-privado" SEF URL. Also check that there's no 301 Redirect created for it. Also make sure that you updated or deleted the old SEF URLs and cleared all caches (in Joomla and JoomSEF) when you updated to new version of the Joomla Tags extension.
What version of Joomla Tags component do you use?

Thank you again. I checked and 301 redirects is empty. On the other hand I have purged the urls, emptying cache, and I'm using joomla 2.1.2 version tags.

This is the old url

mediatoris.com/index.php?option=com_tag&...privado&view=tag

The sef url

mediatoris.com/tag/capital-privado

I couldn't find the 2.1.2 version, I only found the 1.3.3: www.joomlatags.org/joomla-tag/joomla-tag-download.html
Could you post a download link for 2.1.2? Thank you.

What happens if you disable SEF completely in Joomla's Global Configuration and use the non-SEF link stored in JoomSEF? (mediatoris.com/index.php?option=com_tag&...privado&view=tag)

My Joomla Tags component version is 1.3.3 y joomla tags extensions 2.1.2. When installing joomla tags component, everything installed fine. When purging the url and emptied the cache, then its redirected to the main url. When JoomSEF disable the tags component works fine.

Could you please contact me at Tato emailová adresa je chráněna před spamboty, abyste ji viděli, povolte JavaScript with access credentials to your website's administration area, so I can check what's going on there? Thank you.