In planning board, you can drag and drop an item to one panel only at a time. Select User Story from Backlog and drop it to the desired Sprint panel. You can then drag the same User Story and drop it to desired Release panel.
However, the recommended method for associating a User Story to Release and Sprint at the same time is via Detail View of Item. To do so open item Details by selecting ellipses menu and select View Details. Add missing Release or Sprint value and save it.