Experienced the same issue, while using a map service in AOGL.
And found the issue to be with Feature access capability options while Publishing the map using ArcMap.
Please select Create,Delete,Update on Feature access tab of Capabilties, by default only Query will be checked.
I am not sure why the editing is not happening if we check the 'Sync' option of Feature access while publishing(so please uncheck Sync).
Hope this helps.