I can't add a link in Numbers

The option to a add a link in numbers is greyed out as seen in the image. I can't use Cmd K etc and I've looked through various threads and it just talks about using format or Cmd K but no way of making them live (ie not greyed out) I've tried this in a new sheet, with an empty cell, a complete cell etc.

Numbers and the MacOS is up to date (Numbers10.0 and Catalina 10.15.4)