Check your country’s official telecom regulator or government SIM-check portal
Use the official mobile network operator apps or websites
Call or visit your mobile operator’s customer service
Visit an authorized telecom service center with your ID
Use any national ID-linked SIM verification service if available
Review all mobile numbers registered under your identity in the official portal
Request a SIM registration report from the telecom authority if offered
If you suspect unauthorized SIMs, ask the operator to block or investigate them