I've had a major issue with QB on my Mac since Apple introduced El Capitan several years ago. I've used DD/MM/YY ever since I started with QB in 2004. After El Capitan, it no longer worked. It was so bad that I bought a new Mac and kept the old one on the old OS and fired it up periodically to use QB. This year I decided to use the MM/DD/YY format just so I could use one machine for everything. Now the situation is worse. I was entering bank information for 2 Nov. I entered 2/11/19 for two entries and they appeared correctly. My third entry (as 2/11/19) was posted as 11 February. I've just tried to update bank information -  trying to post an interest deposit to a savings account dated 30 Sep. It doesn't matter if I type in 30/9/19 or 9/30/19 because as soon as I hit the tab to move to the next section on the account, the date is changed to 04/12/19! Can't understand how QB worked for over 10 years; and now won't work at all. Is there any help???

Now running MacOS 10.15.2 (Catalina) with QB 2019 for Mac V18.0.6 R7