Generally, freshmen will change their numbers when they arrive at school. He may have changed his number. Also, the requirement of military training in Chang 'an University is not to turn off the mobile phone, but many people will secretly bring it, but it is silent. So he is more likely to change his number. Just wait for him to contact you, or use qq to find him. If you can't contact, I suggest you call the counselor. There should be no problem. The campus environment of Chang 'an University is quite good, and the environment is quite simple. There is hardly anything to be afraid of. During military training, I often check the bed during the day and call the roll every day. If someone disappears, they will find me immediately and contact my parents. Don't worry too much. Maybe he was just careless.