Thanks for the test environment.
We can find the cause of the problem.
As we can see, on your site the normal WooCommerce templates are overriden, and the applied custom template does not use the same css class convention than the original WooCommerce template.
Namely it does not contain the wc-tabs class, and it is needed our plugin to work correctly.
The original WC template contains this line:
<ul class="tabs wc-tabs">
Your template contains the following line instead:
<ul class="tabs">
In wp-content/plugins/woocommerce-custom-tabs-pro/js/wct-single-product.js file you can find the following lines:
//On descendants of .wc-tabs class should not been active this function, because it caused infinite loop.
if($(e.target).closest('.wc-tabs').length)
return;
Please edit this file, and insert the following lines below the above mentioned lines:
if($(e.target).closest('.woocommerce-tabs').length)
return;
if($(e.target).closest('.wc-tabs-wrapper').length)
return;If this solve the problem, please let us know, and we will insert these lines into the next version. Since then you can use the plugin with the modification that you made.