giwrgos74 Hi. I know that. I only asked where should they be located on Your site since I do not understand Greek language. But I've compared one of other templates and found the place via source code and I think Pavit's suggestion was right, the only thing I would add it would be to narrow the selection of this css class to this registration form only, so please add this to custom.css file:
.registration .modal {
position: relative !important;
display: inline-block !important;
}
I believe a fix to this in all templates will be to add a similar class, already tried that in developer tool and it worked.