Auto-Complete stopped working

I use auto complete in two projects. It still works on one, but not the second. I’ve made no changes to the long lists. I’m using auto complete every day for work as a novelist, and it’s a time saver not having to write more than the first one or two letters of a word.
Any help would be appreciated.

I think that you may have answered this question yourself on 14 February - is this not the same problem?