Redmi main display card 2 can't detect the sim card! What to do!

If your mobile phone cannot read cards or detect SIM cards, the following situations may occur:

1. Insufficient contact between the mobile phone card and the metal contact of the mobile phone.

Second, the mobile phone card is damaged.

Third, the location is a signal blind spot or there is no signal suddenly.

4. You can try the card on other mobile phones, and judge whether it is a card problem or a mobile phone problem by changing the card for the mobile phone.