Why can't the mobile phone send text messages when the plane takes off and lands?

Shut down for 3 hours. Please leave a message and send it to a circle of friends:

1, the plane is ready to fly, and it will stop for three hours. Please leave me a message if you need to contact me!

2. I want to start my own plane trip, and I will turn it off for about three hours. Please send me a message as soon as possible if there is something important!

3. Sorry for the inconvenience. The plane will be closed for three hours. Please leave a message. I hope you can wait a little longer!

4, power off for 3 hours, please leave a message, please don't bother me, I want to make my world quiet!

If you need me, please leave a message and turn it off for 3 hours. Thank you for your patience!