Why do I have to dial these numbers to disable carrier & select SIMBA as a carrier? February 17, 2023 07:22 Updated This is only for certain types of handsets where the VoLTE functionality is locked on the phone by default. Related articles I could make calls when I was with my previous service provider. Why can’t I make calls now? What are the supported devices? How do I enable VoLTE? What is VoLTE? How is SIMBA Network Coverage?