The combination code update procedure on the lock happens when a user with permission to lock/unlock (authorized user) connect to the lock with their phone. This could be the owner of the lock or someone who has been shared access with. However if you change the code on the app, the code on the lock won't be affect until you or an authorized user connect to the lock.
In other words, someone (with authorization) has to go to the lock physically and connect to it to update the code on the lock.
Please note that the lock connect connect directly to internet and the only communication channel is through Bluetooth to a nearby phone.