Cannot add column separator

I am using LO version Version: 6.1.4.2 (x64) on Windows 10. I have a simple text list that I formatted into columns (via Format>Page, then selecting two Columns). I wish to add a line separator between the two columns, but I have been unable to do this. When I go to the lower part of the Format Page screen and click on Style under Separator line, my only choice is -none-. What am I missing?

Thank you for any help!

Using Windows7/LO 6.0 I find that if you open the Separator Line>Style list it will appear to contain only none. But if you hover your mouse pointer just under the none you will see there is a line shown, just so thin as to be invisible. Click to select it and go on to select a decent line thickness and colour and all will be visible. I expect the other spaces might reveal other styles of line, but I have not explored to find out.

Thank you!! I doubt I would have discovered the solution without your help.

Your welcome – we all fail to spot something simple now and then. And thank you, it is nice to hear that our suggestions have helped.