Eshop not searching. Always goes back to main page without search results

On the main search page of Eshop, when I put in a search term and press search, it just brings me back to the main page without searching. page also opens to filters expanded and not to collapsed.. This is a huge problem.
Joomla! 3.8.8 Stable
PHP 7.0
EShop version 3.0.3
www.sunrisehelicopter.com/parts

Hello Rob,

I resolved the problem for you and answered you via ticket system. The reason because you didn't choose the default menu item for your store.

Please check the results again and get back to me via ticket system.

Sincerely, Giang