[Plugin: Gengo] Tags does not translate

I do not know the reason why some tags are shown translated while others not. This is my blog in english:

https://www.gelo.tv/blog/en/

Yo can find in the home page tags like “realidad aumentada”, that are spanish, but a translation for this tag has been provided in the admin area so it should show “augmented reality”. Some times tags are shown in english or spanish due to unknown reasons. For example, this post shows the tag “ciudad” in the home page, but its translation “city” as an individual entry:

https://www.gelo.tv/blog/archivo/urban-flickrs-2.xhtml/en/

Greetings!