My mobile phone is Tianyu c235. I want to set the SMS password today. I didn't expect to press the wrong button later, but I didn't find it and I didn't know the settings.

The SIM card is locked, so you need to enter a PIN code, usually 1234. If the PIN code is entered incorrectly for three consecutive times, you need to enter the PUK code. Generally speaking, the PUK code is on the user card, or you can check it in the operator's office. You can call 10086, 100 10, or check online, provided you know the password. If you don't have a password, go to the business hall and bring your ID card. If there is nothing, it will be very troublesome. PUK code is difficult to guess and crack. If the SIM card is entered incorrectly for ten times, it will be self-destructed and scrapped.

If the card is scrapped, go to the business hall to reissue it. With your registered ID card or user password, if there is nothing, it cannot be replaced. You must pay for the new card. Some places are free, and some places may charge 10-50 yuan. After changing the card, the number remains unchanged, the phone bill remains unchanged, and the customized service remains unchanged. It's just that the original phone and text messages on the card can't be found.