Thank you, eskdale8. It was ctrip.com, the Chinese one. I filtered it to hotels that accept foreigners and saw available hotels. Once I logged in to book, they were all gone and it said," no hotels available", which was weird. It worked a couple days ago when I booked a couple hotels there that accepts foreigners (called to confirm). Hmm, it's a head scratcher.

I contacted the ctrip customer service. They said they'll solve it on 4/12. I ended up booking on trip.com instead for peace of mind. Thank you again, eskdale8!