It may be caused by the confusion of China Unicom's business adjustment. For example, this may be the ring tone service you opened before, which was free of charge during the event, but now it is charged.

However, China Unicom did not provide any information notification, and you did not use this service. The responsibility lies entirely with China Unicom. You can call customer service to explain the situation and request a refund of the balance.

You can spend 1,000 yuan a month, but before that, you must get back the 1 cent you deducted for no reason! Consumer tolerance will only make these opaque phenomena darker.