The service is only available to Safaricom subscribers, so make sure that your SIM card is updated.

Dial** 62*0722199199# and you will receive a notification that the services have been activated.

If you want to deactivate missed call alert , you only need to dial ##62#. It is even simpler cramming the numbers.

ALSO READ  How to send “please call me” text message on Safaricom, Telkom, and Airtel