Easy Table Content: problem with font size

Hello!
I have installed the easy table content plugin to create automatic indexes on my page.

From the plugin administrator I have been able to modify the size of the font, but it is not changed on one of the pages.

The page:
https://manualdesnowboard.es/aprender-snowboard/

It seems that the table of contents is taking the size of the H2s. I don’t want this, I want it to be “standard” as in the other pages, following the plug-in configuration, on this page it looks as I want:

https://manualdesnowboard.es/tablas-snowboard/

How can I do it?

Thank you very much for your attention, greetings!

The page I need help with: [log in to see the link]