Now most mobile phones are smart phones, similar to computers. If you don't shut down and restart for a long time, the system may encounter various problems, such as slow card, no SMS, software flash, no SMS and so on. In this case, just restart the phone.
Nowadays, many people have two cards and use one mobile phone, and sometimes they can't receive short messages. It is suggested to replace the card slots of two cards to see if they can receive short messages normally.