{toc} macro causes NullPointerException on space export

From within Confluence, the

{toc} macro works perfectly with the {include} macro on the same page. However, when the space is exported in HTML format, the HTML page shows an error in place of the {toc}

macro:

Error formatting

{toc}

macro: NullPointerException

The PDF / Word export from the Info tab also do not work properly. The links in the PDF are not clickable. The Word export always prompts with the types of 'Convert File from...' HTML, RTF etc. HTML generates the same NPE as above, while the RTF conversion is not at all possible, it just breaks with an error as shown in the attached screenshot..

Can someone please address this issue on top priority? I need this to be working very urgently.