Using Classic Outlook on Windows for personal email, calendar, and contact management
Jamil Haddadin, thank you! I think this finally fixed it. To be clear, I have a apple watch and iphone 5SE. Both are up to date as to software. I had already removed reminders from both devices, turned off notifications, to no avail.
I went to settings, passwords & accounts, chose the account on which I have tasks (I have 3 accounts), and slid reminders to off. I left calendars, emails, contacts on. Then I re-categorized everything, for the umpteenth time. In the past, the task categories were disappearing about 9:00 am. It is now 9:30, and so far everything is good today.