Everything that you should know about registration of mobile devices for Kcell and Activ subscribers
According to the law requirement, from January 01, 2019 all operators of cellular communication in Kazakhstan shall not have the right to provide communication services on unregistered subscriber devices.
Inserting a SIM-card to the unregistered device, you will receive SMS on necessity of registration of the device. At that you will not have possibility to accept or make calls, send SMS to other numbers except the number 6006. It is possible to use the mobile internet only for carrying out of registration.
More information and answers on your questions, you can find here.