The cause is one of the followings. (Android)

 

1

When updating OS of the smartphone device to the latest version, the updated OS might not be able to support the older version of application. 
Please make sure to update application to the latest version before using.
Latest version can be checked here.

 

2

「USB debugging mode」 might be turned ON.
Please turn OFF 「USB debugging mode」 before opening the application.

 

【Updated on 5/7/2021, 16:40】

Releasing of My Entrance V1.1.2 which fixes an issue of the application not able to be opened from V1.1.1. 
Please update the application via Google Play Store or the link below.

We are truly sorry for any inconvenience this may have caused and thank you for the continuing support. 

■ The application can be updated by visiting the link below.

 

【Important matter on 2/7/2021】

Currently, there is an abnormality in My Entrance V1.1.1 (Android) in which the security tool in the application is activated by mistake which results in failure to open the application.

While the revised version of the application is being prepared, it is recommended to use other types of key for the time being. (Such as manual key or key card)

We are doing our best to solve the occurring issue as fast as we can.

We are truly sorry for the inconvenience this may have caused.