The issue with the retention policy concerns only the sync (it should be fixed for the next version of Tasks).
To workaround it it is enough to use any option, different from Manual delete only
When was the last time you have successfully synced? Two other users reported similar connection issues, so we are revising the applied server-side update.
Could you, please send us your username for the Telerik cloud sync service in order to verify there is nothing wrong into your account?
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