There are 2 registration methods for customers to choose from. 
①Method that involves registering the currently used key card along with the additional one(s)
How to register or delete key card/tag key/mobile wallet/EVERING
②Method that allows the user to register only the additional key card(s)
How to register additional remote control/key card/tag key/mobile wallet/EVERING
※Registration data of remote controls or smartphones will not be deleted when registering key cards.