I just had the weirdest thing happen on my iPhone 6s. I'm running iOS 10.0.2 and while I was sitting in my office, my phone lit up stating that a location in China is trying to access my Apple ID, I denied the access, but shortly after my phone started acting really crazy. No weird text messages or anything, but my iCloud/Apple ID was locked, I changed my password twice and tried to sign back in after unlocking and no luck. My location services also drained my battery in about 20 minutes from 98% to 39%.
What is going on? What should I do to reset everything and get my phone back to normal?