my concern is does the bank have that authority to stop my cousin from taking money out from his account and give such reason or excuses ?
banks have this authority. In my country, banks have blocked the accounts of many people until these people file income statements, and this is causing problems for many people because most of the people in my country do informal business. This problem will worsen when involves bitcoin. how would people say that source of income come from bitcoin? so we need clear regulations on bitcoin
is there any legal solution ? is it possible to sue the bank ?
just deliver what the bank is asking