Unicom can get a refund if it unsubscribes without using voice packets.

I can't. Unicom voice agreement stipulates that once Unicom voice package is purchased, it is not allowed to unsubscribe. China Unicom is mainly engaged in fixed communication services, mobile communication services, domestic and international communication facilities services, data communication services, network access services, various telecom value-added services and system integration services related to communication information services.