UPDATE: Sweet for ArcGIS Online Locking Server Intermittent Outage - RESOLVED
/We are currently experiencing an intermittent problem which affects all customers using Sweet for ArcGIS Online. The behaviour a customer will see is that there will be no locks communicated by apps. This means users will be able to edit in the same area without being notified of each other’s edits.
Our product team is working to resolve this issue as soon as possible.
UPDATE:
Issue resolved at 16:00 28/09/2021