This error you get when validating the ESEF package with a tool like Arelle means the block tagging is applied incorrectly.
When you use a tag more than once in your document, the XBRL standard specifies that it should be chained: the first tag should specify where it is continued. This is implemented in Tangelo, and functions as dictated by the standard when you are using a tag multiple times throughout your document.
If you are getting this error, it is most likely that you are using a tag within itself. This results in a continuation chain where an element in a chain refers to an element within itself.
See for example the situation below:
If you tag the Subparagraph with a certain tag, this means that it and all its content (including any Subsubparagraphs contained within) are part of that tag. So there is no need to apply tags like this, and to fix the error you should remove the "inner" block tag.