Break Dance Builder

Hello,

I have this website with Break Dance Builder.
I have an issue with search form.

Form action in Greek

<form role="search" method="get" data-type="classic" class="js-search-form search-form search-form--classic" action="/">

Form action in English

<form role="search" method="get" data-type="classic" class="js-search-form search-form search-form--classic" action="/en/">

By default when I create the English header the form has same action with Greek. This resulted in the search only working for the Greek content.

I change the action with custom code.
However, do you know how can this be fixed?
Where did it come from?

Thank you!

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