i'm working in Automation Studio in order to duplicate the data of synchronized DE into a new sendable DE. The problem I have is that I see the synchronized DE in Contact Builder but I can't find it when I try to create the query (the synchr DE folder is empty). Which could be the issue and how can I solve it? In addition, as the sendable DE Id like to create should contain the list of all contacts i wonder which are the best option for creating the query: scheduling hourly with "add & update" is correct? I'd really appreciate any best practice you'd like to share with me. thanks so much Lucia