How to cancel the mobile phone card?

Take Unicom mobile phone business hall as an example. You can cancel the calling card on your mobile phone. The method is as follows: 1. First, open the Unicom mobile phone business hall, and click the service below. 2. Find the processing on the left; 3. Then pull to the bottom to see the final account closing function; 4. Then select the reason for canceling the account, and click Next; 5. Click Next after checking and agreeing on the account cancellation notice page, and then complete the cancellation through SMS verification code verification. The number used in China is 1 1 digit, in which each segment has a different coding direction: the first three digits are network identification numbers; The 4th-7th digits are the area code; The number 8- 1 1 is the subscriber number. This number is the so-called MDN number, that is, the number that the calling user needs to dial when calling the mobile user of this network, and it adopts E. 164 coding mode; Stored in HLR and VLR, and transmitted on the map interface.