I am using the collector app on iOS. Over the last 2 weeks, my users have been getting the "unable to open map file not found error" with their downloaded offline areas. This error has affected all of my users, some more than once. Sync still works for some reason on affected offline areas but, my users are not able to use their maps until they remove the downloaded area and re-download the area again. Is there anything that could be causing this issue?