I have a lot of projects on ArcGIS Online (AGOL), I've had years of success with making a local copy, editing it, and pushing it back up to AGOL. However recently I've been getting a message about 50% of time when I go to re-sync the edits "The local edits were not synchronized to the server. Authentication token required. (status code 499). Needless to say this is very frustrating and copies of the data are left un-synced.