Hi nilb,
There are multiple issues with your tracking codes in your site which are needed to be solved before you can start tracking any clicks and other events:
#1 There is a Universal Analytics code snippet just after the <title> tag hard coded in your site, this should be remove if you want to track everything with Google Tag Manager
#2 There is a classic Analytics tracking code just below the code in #1 which has been added by the plugin called “start/ Premium SEO pack” – this should be removed as well
#3 The GTM container code placement seems to be set to “footer” but you also added the manual code to the header which cases GTM to load twice on your page. Please remove this additional code and switch to “codeless” option, it should work on your site.
After this you will need to add a general Google Analytics tag to your GTM container so that your GA account can continue to collect pageview data.
If you have managed to get to this point, we can continue with the required settings to track clicks on your banners.
Cheers,
Thomas