Whenever I close and open my Outlook, the settings that can be found under "File > Options > Outlook Options" keep changing. I have posted my current OS and Office version below. I have also listed down the following settings that keep changing.
OS: Windows 10 20H2
Application: Microsoft Office Outlook 2016
Settings that keep changing from check to uncheck and uncheck to check:
1. File > Options > Outlook Options > Advanced > Outlook Panes > Reading Pane... > Mark Item as read when selection changes
2. File > Options > Outlook Options > Mail > Save Messages > Save copies of messages in the Sent Items folder
3. File > Options > Outlook Options > Mail > Send Messages > Use Auto-Complete List to suggest names when typing in the To, Cc, and Bcc lines
NOTE: When I reinstalled my office 2016, it was working well. But after updating office, the problem comes back again.