When creating a Q&A pair or Faq Item each must have a unique access key. The access key in technical terms is the "Anchor" used to find that particular Question/Answer pair on the page.

It becomes part of the URL to access the item in the following form
http://www.example.com/faq/#access-key-here

The key should only consist of letters and numbers, no spaces or any other punctuation, and for best search engine indexing it should be a key-phrase related to the question/answer being defined.