In VietNam. They know The Goverment not allow for casino online. So They can lock any player without meet any problem.
It seems like the issue here lies in the fact that you knew gambling was illegal in your country, yet you still participated. Also, the amount of money involved isn't that large, just over 100 USD when converted. The company likely spends a lot on promotions, so it's doubtful they'd risk their reputation over such a small amount.
There’s always a risk when playing games that are prohibited in your country, and you're experiencing that now. Plus, you can't call a company a scam if they're simply enforcing their rules.