Hello GJ2020,
Thanks for your post here.
Firstly, If someone suggested you contact the support via phone number, it is a spam and please ignore the spam or report it. We are monitoring our forum to avoid the spam. And we will have actions for these replies immediately once we notice them.
From your description, I understand that the formatting marks will be turned off automatically in Outlook. Based on my knowledge and test, the formatting marks will be always turned on when I select the option. Given your situation, please try the following suggestions to see if it works for you:
1. As a workaround, please try checking all options in Editor Options and then check the result.
2. Repair Outlook by following the steps in this article: Repair an Office application.
3. If quick repairing cannot work, you can uninstall it and then download it again to see the result.
If the problem still persists, please kindly provide the screenshot about your Outlook product information to me. To get it, please click File > Office Account, please capture the screenshot under Product Information section and share it with me.
Thanks for your time and I will try my best to help you.
Regards,
Seven