We have received info from Post, that starting from Jan 1st posts will stop accept small packages sent as registered letters. It was way how we shipped most small orders in Europe. For some countries it was only available shipping method.
Due to this change we have suspended accepting orders with this shipping. That means we service now lower number of countries. We are looking for solution. Post proposes use of parcels instead, but price is about 3 times higher so courier services will be in similar price or even cheaper.