I received a blank message in the middle of the night. I don't know who it is. What do you mean, nothing?

If the number is a mobile phone number, someone may have sent you a multimedia message, but the transmission failed, or a liar or something sent you but didn't send it. If it is not a mobile phone number, it is sent to you by the service desk. You can check whether you have subscribed to any services. If not, it may be a small group that sends advertisements in groups (debugging equipment and the like). At present, our mobile phone number has no privacy at all. If you register your mobile phone number on some occasions (such as online registration), it will be exposed, so it is normal to receive messy information. As long as you insist that you are not the person you know or the service you apply for, you will ignore everything else.