Why Does It Say Invalid Sim Link

SIM cards can wear out or get scratched over time.

The device is good, but the setup experience soured the unboxing. I am rating this 3 stars due to the headache of resolving the carrier compatibility issues that should have been handled before the sale. why does it say invalid sim

In my specific case, the error was caused by an IMSI mismatch . The phone was an international variant that was not fully whitelisted for my US carrier's network. The SIM card was valid, but the phone's software didn't have the correct configuration files (APN settings) to handshake with the tower, defaulting to an "Invalid" error. SIM cards can wear out or get scratched over time

Skin oils or dust on the SIM’s gold chip can block the signal. why does it say invalid sim