Hi,
It could be that you selected another zone that the Hungary zone country.
For example, if you created a shipping zone for Hungary, and you didn't add the Hungary country zone as a sub zone of the shipping zone, and then you selected that shipping zone in the zone restriction of your shipping method, the system won't be able to link the country zone of the address of the user with the shipping zone of the shipping method.
In that case, the simplest is to directly select the country zone in the shipping method.
Also, if you restrict a shipping method to a country, the shipping method will only appear on the checkout after the user has provided his shipping address with that country selected. If you configured your checkout workflow to display the address view and the shipping view on the same step and there are no other shipping methods available for the user, you'll get an error message.
Also, it could come from another restriction in your shipping method. So that's something to check too.
We have a section about what to check in our FAQ:
www.hikashop.com/support/documentation/106-faq.html#ship