Korea kt card can't use the call function.

Korea kt card can't use the call function. Solution:

1. Under the standby desktop-click Application-Settings-More Networks/More Settings-Mobile Network-Network Operator-Search Network-Select the network operator supported by your SIM card;

2. Take out the KT card and clean the metal contacts of the KT card with rubber. (whether it is poor contact of KT card);

3. Try to replace a KT card (regardless of whether the KT card is aging or damaged);

4. Check whether the mobile phone is equipped with software such as security guards or incoming calls, uninstall it and try again.