Time stamp on the smartphone and time stamp recorded in the door's built-in hardware are not aligned with each other.
Displayed time stamp on the application is varied upon the type of operation.
・Smartphone Operation： Time displayed on smartphone device
・Every Operation, Settings Change etc.： Time recorded on the door's built-in hardware

When difference in operation time stamp is longer than a certain limit (approximately more than 5 minutes), said difference will be automatically corrected when smartphone is connected to the door. 
However, the difference will not be corrected if it does not exceed the limit.