garmin coach re-schedule activity and it disappeared.

I'm using garmin coach. I re-schedule my activity and it disappeared. I first did it from the mobile app, and disappeared. I then try to turn off my venu 3s, clear the cache in the mobile app, try to visualize from the web app. The activity I re-schedule disappeared completely from my monthly plan. To confirm the error I try to re-schedule from the web app another activity that I have from Monday to Tuesday. And it also disappeared from everywhere. Couldn't fix it. So I exit the garmin plan, and create a new one. In the past month I was able to re-schedule without problems, not sure what changed from last month to this month.