Before binding the NB module, please make sure that the NB module is equipped with the minimum system circuit. The power supply is stable, the antenna compliance signal strength is good, and the NB dedicated IoT SIM card has been inserted.
The NB module is not activated before it is used for the first time after leaving the factory. At this time, the binding using the Tuya App will fail, and the activation must be completed after the first network connection.

Module activation steps:

The module is powered, and the MCU interacts with the module.
The module will send a 01 command word to the MCU to query the product PID.
MCU responds to the product information query command sent by the module.
The module receives the product information and uploads it to the cloud to activate the module.
Network status 03 (connected to the telecommunications platform, the device is not bound)
At this time, Tuya App can be used to scan the module shortcode tag to bind the device.
After the App is bound, the device must interact with Tuya Cloud once before it can synchronize the bound messages. You can interact with Tuya Cloud by actively reporting a piece of data or MCU sending a reset command to the module. The successfully synchronized module will send out a bound network status notification. The NB module has strong binding. Once bound by a user, the device must be removed through the App to bind other users. The local reset command on the device cannot be unbound.

The module short code label is the unique identification code of Tuya NB module, and the non-module comes with a production label, which is generally affixed to the outer packaging of the whole machine, which is convenient for terminal customers to bind and use. This label must use the Tuya label printing tool to generate the label, the tool can be obtained from the Tuya's staff. In the development stage, you can manually enter the module IMEI binding.