About: http://webisa.webdatacommons.org/284380865

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	It looks like it came from a Word document.I think that is what is causing all your problems, including not being able to change your heading to a paragraph.I think that the best thing to do is to start again with your article.
http://www.w3.org/ns/prov#wasQuotedFrom	joomla.org