What does it mean to sign a bank card SMS for 30 days free?

30 yuan refers to the short message service in 30 yuan for one year. The short message service fee refers to the short message prompt sent by the bank to the consumer when the funds in the consumer's bank account change. The short message service fee in 30 yuan refers to the short message service on the bank card handled by the user at the bank, and the service fee in 30 yuan is one year.