Download a software on your mobile phone and send a message to others casually.

This may be a cliche, but it does make sense.

Download and install the software to a regular app store.

Don't install software you don't understand at will.

The software can have as few permissions as possible.

Don't wait for the loss to be recovered before you study.

In your case, if it is serious, this message may be caused by some verification codes, and the consequences may be that the account number is stolen, the bank card is stolen and so on.