A program that grants points for using Bing search, which users can redeem for gift cards, sweepstakes entries, or charitable donations.
Sorry to hear you're having trouble.
It seems as though you've already contacted the Rewards Support Team via the form located here https://rewards.bing.com/support. I'm afraid that is the best option to get help regarding Rewards issues. However, you did mention that your VPN is turned off. That makes me wonder if you'd had it turned on while completing some quests.
If this is the case then it may be that the points you earned during that time may not be eligible. My suggestion here would be to contact them again but suggest this possibility and be sure to ask if they can make sure your account and all available rewards are set properly to the US.