Ignoring default font setting, reverting to Arial 24 pt each time a new text entered.

Arial 24 pt jumps in  every time I click for a new text entry despite default size is set to Arial 12 (X7 Version 17.6 on Windows 10 Pro ).
Pressing F8 when nothing selected properly shows Arial 12 pt, but as soon as I click to the page for actual new text entry it reverts back to Arial 24 pt. I need then manually set it to 12 pt each time. Restarting computer or updating to a new version does not help.

It is quite annoying feature, please help.