I only encounter the 2-hours lockout because of not using indian VPN to login, and it will only lock me for around 2 hours so far. Never tried to have yours like locking for overnight. And reinstalling/unlinking should not be working as there should have some data stored on the NBA side everytime you login, so you uninstall on the client side cant help at all.
I turn off VPN everytime during watching games and so far no problem if the game duration is within 2 hours. Several time that the game have OT/longer than 2 hours, they will lock me up. So I guess their checking algorithms is like
1) check the record on their side for your NBA account, whether is recorded in indian, if yes then good to go. If no record, then check your ip at that moment. And of course if there are record showing you are not from indian ip, then you are locked up. And this process will repeat every 2 hours, so when you are watching long game over 2 hours, you will be blocked after 2 hours from your first login.