Web Browser not loading Reminders

Hello, I'm new here! Issue... on my windows surface pro3, all the web browsers fail to load the Reminders app which produces (Error code: Out of Memory). Icloud used memory is only 3G out of 5G available. I logged in/out of everything turned Reminders App on/off from iPhone11 Pro. Problem just started a few weeks ago. There was a previous error last week (Hung_Process) I believe. Any assist is much appreciated!