Change default option

-- url of the page with the problem -- : www.ododo.gr/
-- HikaShop version -- : 4.5.1
-- Joomla version -- : 3.10
-- PHP version -- : 7.4.27

Hello,

I select a product on Specifications->Options in Product Page Back-End.

In the Front-End added o dropdown selection with two options for this product. Please see the attached image.

I would like to change the default option, which now is NO with the other Option, Yes ( +0,70euro ).

May you can help me?

Thanks in advance