Joke Collection Website - Public benefit messages - What if the signal is not good in rainy days and the other party can't receive the message?

What if the signal is not good in rainy days and the other party can't receive the message?

Usually, our students' special method is that you send a message, and you are not sure whether the other party didn't receive it or the other party replied. You can do this when you don't receive it yourself.

1: Call the other party and hang up after the bell rings, so that if the other party doesn't receive it at first, it can receive it now.

Call yourself to check the balance, so that if you don't receive the reply from the other party, you can receive it now.