Cloudkit - coredatat - duplicate row on tableview

I have switch my database with cloudkit function.

I have two iPads : after few tests, the database was synchronize between the two devices.

But after checking all data, in one view, there are duplicate rows, : with the same UUID !!! This error is not present in all views, just few ones...and I do only fetch for the moment, no create data

in debug the fetch show duplicate values, why I do not understand this behavior because on my database before using two ipad, I had only one Record for a element not twice???

myarray = try moc.fetch(ReferencesRequest)

same record present twice in the array after fetch