| Category | Specific Cause | Description | |----------|----------------|-------------| | | Poor contact / dirt | Dust or misalignment prevents electrical connection | | | Physical damage | Scratched, bent, or broken chip contacts | | | SIM not fully inserted | Tray not closed properly or SIM loose | | Carrier & Account | SIM deactivated | Carrier disabled SIM due to non-payment, reported lost, or account change | | | SIM not activated for new line | Brand-new SIM not registered on network | | | Carrier lock conflict | Phone locked to another carrier; SIM from different carrier rejected | | Software & Settings | Outdated carrier settings | Missing or corrupted network configuration | | | iOS/Android bug | Software update glitch or corrupted network profile | | | Airplane mode or network lock enabled | Incorrect settings prevent SIM detection | | Hardware Failure | SIM tray reader damaged | Bent pins inside phone’s SIM slot | | | Motherboard issue | Faulty SIM card reader circuitry |
If the digital quick fixes don't work, the problem may be the card itself: If you see 'invalid SIM' or 'no SIM' on your iPhone or iPad why is my phone saying invalid sim