You might have to add a ‘Date recognition pattern’ to your LibO.
For more detail, please refer to number 3) of my answer in this thread a few minutes ago.
If this does not work you will need to switch off the ‘Use replacement table’ option for ‘AutoCorrect’ (maybe temporarily) or delete some specific replacements there. These are working “on the fly” while typing and their application will precede the recognition/conversion process.
(Down with silly smart features! They always will be incompatible in one way or another.)