I am connected to
Server Location: North America
Node Mode: Basic Mode
Selected Mudfish Node: US West (Oregon - Google)
but when I am logged in to Maplstory, I get disconnected after a few minutes of gameplay with the error “You have been banned by Nexon Game Security for suspicious game or client behaviour.” Each time, I would have to reactivate my account. This has happened over 10 times.
Please advise.
Could you please confirm that it’s also same with Full VPN mode enabled?
If it’s even same with Full VPN mode, it means that Nexon knows you’re connecting the game via VPN. 
not only this game it looks many games like that happen.
Are you meaning that it’s even same with Full VPN mode enabled? Then please try to change Connection Protocols to TCP based. Sometimes MTU (Maximum Transmission Unit) could cause this issue.