fix invalid mmi code ussd

Banking & USSD Codes

Emergency Guide: Block Stolen Cards & Fix USSD Errors (2026)

​Lost your phone? Learn how to block stolen bank cards and accounts using USSD from any phone. Plus, fix “Invalid MMI Code” errors with our 2026 Nigerian guide. This is a complete guide. Emergency Guide: Block Stolen Cards & Fix USSD Errors (2026) ​Now let’s Picture this scenario: You are navigating through the busy traffic at Plaza in Uyo, or…