This feature is especially useful for very large or multi-level houses whose blinds aren't in range to all Smart Controller devices you have in your account.
Tap on the room you want to change the assigned Smart Controller.

On the upper right corner, tap on the pencil icon.

Tap on the Assign Smart Controller dropdown to access the Smart Controller list. Choose the serial number of the closest Smart Controller to the room you are assigning it to. The serial number of the Smart Controller is written on its label.

