I have been playing Pokémon Go since August 2016. I am currently level 18. During Christmas break, I visited China. I decided to see if Pokémon Go works there. I opened the app and found that I was able to log in. I played for a little while as I was waiting for dinner.
After that, however, I was unable to open my Pokémon Go app even after I came back to the US. I have deleted the app and reinstalled it, but still cannot open the app. When I click on the app, the Niantic logo appears for a few seconds but disappears. I did everything from closing all the apps to deleting and reinstalling the app. Now it is not working. How do I play again?