Can't connect text boxes across pages

I have two text boxes on different, but consecutive pages. For each text box, I did the following:

1. Open Object Properties dialog
2. Select Text Frame
3. Set Flow Tag: C
4. Select Autoconnect
5. Click Apply

I then Ctrl + Clicked to select each text box.

I then selected Format > Customize Layout > Connect Text frames.

I’m still getting the following error: This Connection is not possible. You may be trying to connect two text frames that would result in a circular text flow, or you may be trying to connect to a PostScript Code text flow.

What am I missing?