woocommerce shop disappears and reappears

Hi!
I have this problem. Almost daily in the morning my shop page doesn’t shop any product. If I make any small change in the settings (Woocommerce – settings) the products reappear. The change in the settings can be any, like the shop address, or exclude a country to sell to.
Does anyone recognizes this problem? And has any solution?

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