What should I do if the China Unicom IoT Card is stopped? It stopped just after recharging and activating it?

Answer: Internet of Things services are all based on post-payment, but there are two payment modes: monthly payment and prepayment. (1) After the monthly payment plan is activated, customers will pay the subscription fee at the end of each billing cycle; in a certain month during use, as long as the SIM card has an "activated" status in that month, the subscription fee will be charged; (2 ) For prepaid tariff plans, customers must pay all subscription fees at the end of the first billing period of activation; for prepaid tariff plans, the prepaid plan in use cannot be changed before the term ends. After the term, customers can specify updates. The rules are to deactivate, automatically renew or modify to another tariff plan; (3) In particular, for the prepaid-single connection type, users can choose to expire when the traffic in the package is used up.