Plugin not working

Hi guys,

we use the plugin to have a restriction for products for customers in Switzerland. If you have the shipping address Germany selected, put something (restricted product) in the cart and switch to Switzerland, the restricted plugins can still be bought. Why is it not working?

You can try it with this product:

https://xn--bserkater-07a.de/shop/gin/farbwechsel/boeser-kater-3er-farbwechsel-gin-tasting-set-geschenkbox-mit-passendem-fever-tree-tonic-water/?v=3a52f3c22ed6

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