Column Guides Are Unlocked But I Still Can't Move Column Guides

I'm using Adobe InDesign CC. I have a three column text frame and I need the middle frame to be just a bit larger than the left and right columns. I have unlocked Column Guides by unchecking View > Grids & Guides > Unlock Column Guides, but with both the Selection Tool and Direct Selection Tool I don't get the cursor changing nor does clicking and dragging on the guide do anything but move the entire text frame.

I have read tutorials with pictures and I see that it's possible, however I must be missing something. Help!