Sometimes the carrier changes network settings, and your phone needs a small file update to keep working.
If you have tried all the steps above and the error persists, it is time to contact your mobile carrier (Verizon, T-Mobile, AT&T, etc.). why does my phone say invalid sim
If your software is outdated, it may be incompatible with recent carrier settings updates. Sometimes the carrier changes network settings, and your
Seeing an "" or " No SIM " message on your phone can be a major disruption, cutting off your ability to make calls, send texts, or use mobile data. This error typically means your device recognizes a card is present but cannot verify it or connect to the network. Common Causes for "Invalid SIM" Errors Seeing an "" or " No SIM "
This is the "moment of truth" to determine if the problem is the card or the phone.