Access Control Systems

What is the difference between TK4100 and EM4200?

Can I control the TTLock Apartment Access Control remotely through the mobile app? If so, what are the requirements and steps for remote control?

What should I do if the electric strike lock malfunctions? How can I repair or replace parts?

What should I do if the TTLock Hotel Access Control malfunctions or fails to unlock? Are there any emergency unlocking methods or backup keys?