There are periods and exclamation points in the box in the upper right corner of Huawei mobile phone.

Indicates that the SIM card cannot recognize it.

If the status bar above the mobile phone displays an icon of SIM card with an exclamation mark on it, it means that the SIM card is not recognized.

The following investigations are recommended:

(1) Do not use a non-standard SIM card or cut the card yourself. Cutting the card can easily cause the SIM card to fail to recognize or damage the mobile phone. I suggest you go to the business hall and change to a standard SIM card.

(2) Please confirm whether the SIM card is placed correctly and whether the gap of the SIM card corresponds to the card slot.

(3) Please confirm whether the surface of the SIM card is dirty. SIM card is used for a long time, and the metal surface is easily oxidized, which may lead to the probability of not knowing the card. I suggest you go to the business hall to replace the new standard SIM card.

(4) Please don't plug and unplug the SIM card when it is turned on. If you insert the SIM card in the power-on state, please restart the phone.