What to do if the physical SIM card shows invalid or unregistered?
- Check if the installation direction is correct. Remove and reinsert the SIM card according to the slot markings.
- Clean the SIM card chip (gently wipe with a clean soft cloth to remove dirt or oxide layers).
- Try replacing with another card slot (if the device supports dual SIM).
- Restart the device and recheck recognition.
- If still not recognized, the SIM card may be damaged.