I have been having a lot of problems with Reminders, although not with Apple Watch but with my other devices. Since I upgraded reminders but am not running Catalina they are now disabled on my iMac. So I was using Reminders on iCloud. But today iCloud web is showing maybe 10% of what is on my IOS devices. I have also been getting messages about "network too slow" from icloud safari web but speedtest shows I have plenty of bandwidth. Just now in Firefox I got the message to the effect that iCloud is having a problem - do you want to send a report to Apple?"
Worked with support. They looked at my phone, iCloud reminders Web and saw the difference. They looked at my account and saw that that data was there. She consulted with a senior analyst and said "they are working on it".