spellcheck in keynote not functioning

I'm using keynote 6.5.3.

If I select 'check document now' option from the edit menu the buttons do not function. The 'Show Spelling' window is selected/ open, but Keynote will only go one or two misspelled words, and despite clicking "ignore", "find next" or "learn" nothing happens even though I know for a fact there are additional misspelled words in the document.

With 'Check Spelling while typing' selected, no spelling errors are highlighted with underlines.

Ive uninstalled and reinstalled keynote.

Any help appreciated.