Autocorrect not working

Hi all
I have a significant list of auto-correct words - words I frequently
misspell, or words that use non-standard characters . However, none of it
seems to work - the other autocorrect options do, but not the word
replacement feature. I have checked and double-checked the settings, and
can't figure it out. The only anomalies I have found are that the language
(English-Australian), while correctly set for Selection, is not set for
either Paragraph or All text. However, it is set correctly in the default
Style, and in the Spelling and Autocorrect dialogues.
Can anyone offer a suggested solution?
I'm running LO 7.0.1.2 x64 on Windows 10.
Thanks
Edwin