Hello, I think there are two possible reasons,
Some functions of the customized device provided by your carrier have been removed. The purpose of this function is to reduce the network maintenance cost of the carrier. The solution is to confirm with the carrier and apply for enabling this function.
The second possibility is that your device is damaged. The solution is to compare the device with another device of the same model and vendor, and then consider whether to buy a new device.
Good luck, friend.