C57 Concealment of the truth

I waited for nearly thirty seconds for Xu Cong's voice, but he still didn't speak. "Xu Cong, I know you're on the other end of the phone. You should speak!"

"Speak up, Xu Cong!" I snarled at the phone, but suddenly hung up. What was his purpose in calling me, and why he didn't say anything after the call.

I hung up the phone and stood on the rooftop