@pratik I never actually had this problem to start with. Reminders has pretty much always just worked the way it's supposed to for me. I've just heard about others having to do that to fix problems with reminders not syncing (or at least trying it. It seems to work sometimes and not others). I have had to sign in and out to deal with other issues in the past. My photos never got messed up though my devices did spend some time basically re-syncing to make sure they were all up to date and such. Photo's on my Mac for example spent a few hours "uploading" photos though I don't think it actually did upload anything, just spent time checking to make sure it's photos matched what was in the cloud.