Bookmarks stopped working

I feel that using this theme, which is very good indeed, I have come across a problem.
My page / post bookmarks seemed to have stopped working. The cTabs plugin that I am using on this page is making use of bookmarks to jump from one part of the page to another.
Since installing the Customzr theme I cannot use them. Look at this page.

https://zenon-education.org.au/resources/%CE%B5%CE%BB%CE%BB%CE%B7%CE%BD%CE%B9%CE%BA%CE%AE-%CE%B3%CE%BB%CF%8E%CF%83%CF%83%CE%B1/h-%CE%B1%CE%BB%CF%86%CE%B1%CE%B2%CE%AE%CF%84%CE%B1/

I have tried de-activating all other plugins and allowed only cTabs plugin to run but still cannot get it to work since I moved to the Customizr Theme.

Can someone help?