Detailed Instructions: In this task, you are given a context tweet and an answer. Your job is to generate a question for the given answer based on the given tweet paragraph. Note that your question should be answerable based on the given tweet, and the answer to your question should be the given answer.
Q: Context: @scooterbraun I beg you please cancel Justin's UK stop. It's for his and many others safety. Please! I'm begging. Mrs.Bieber (@madi_emblem3) May 24, 2017 Answer: justin's.
A:
who's tour does the author want canceled?