In fact, if the government could, it would have banned it by itself.  But what will happen if the government bans, everything is in the hands of the people.  Like Bitcoin is banned in our country but we are using it secretly.  Bitcoin has spread across the world in such a way that it can never be eradicated.
People are now leaning towards the modern age.  Meanwhile, the use of paper money has increased the amount of money online.  At this time, if the government wants to stop this bitcoin, then the internet system has to be down from all over the world.  Then Bitcoin may be banned.  But this is not possible for governments in any way which is why Bitcoin will never stop.  If the government wants to, the state director government of the country can ban Bitcoin in that area.  But people will use it secretly it can never be denied like Bitcoin is illegal in our country but we have been using it secretly.