Mobile checkout redirects to normal checkout

Hi,
The sidebar cart and checkout works perfectly on desktop.https://new.beicustil.ro/
But on mobile, after I click on the icon, I get the popup (you gave me an updated version on a google drive link as this didn’t work before), then the issue comes when I click on the checkout button in the sidebar cart, instead of getting the next sidebars (address, payment, etc.) as on desktop, it redirects me to the normal woocommerce checkout page and the sidebar closes.
Please advise how can we have it working as on desktop.
Thanks!
Sebastian