Hello, we are using Remote Event Receivers (Asynchronous) in our SharePoint add-in (provider hosted) for performing some post-processing on document library items. However, everything works fine overall, but once in a while the events are just not triggered.
Also, this is being observed only on SharePoint Online, the behaviour is not observed on SharePoint On-Prem.
Yes, I have experienced this. More specifically, on lists, and seemingly more often on the ItemAttachmentAdded event than the others. Seems like the idea is to not use RER's, and wait for web hooks to roll out (not a great answer in the meantime).