If there are multiple laws:
a) in a country (all the laws in one country)
b) in multilple different countries and / or multinational unions (all laws in different entities, e.g. all in a different country)
that contradict each other, what is a person supposed to do to follow the law? Those are two separate questions: a), b).
I prefer to discuss these questions in general.
example of b) Mr. Peter is a cook. He intends to become a solo entrepreneuer, have employees, in two different European Union countries and sell e.g. pizzas on a busy place. According to the both countries' law, he has to pay a health insurance in each country, where he is a solo entrepreneur. But according to the European Union law, the maximum number of countries to pay health insurance is at most one.