No sub categories visible "incorrect leaf" error

[365 Lighting]

Hello,

 

I'm unable to allocate my products to the required sub categories. I only have the upper level category visible. See attached pictures for the error & my attempt to fix the problem.

 

I did see a pinned topic regarding the categories not displaying however this was posted a while ago and I don't think it's now relevant with Version: 1.8.1. I attempted to update the code in ebay.php however I get a syntax error (I thought that // is meant for notes and not read by the browser).

 

Please help as I've really cannot see any way around this problem.