Need help with a UML case-class diagram

[League of trollers]

So i have a scenario of a buyer who make an order on a seller of a bank  . I need their personal info to be sended to the bank. Should i make an Actor bank with a connection:SEND INFO? i asked my teacher and she said something like you should be careful at this exact thing. so it made me curious.

Also about the class diagram, How should i send their info on the bank? should i make a class bank and a method SEND INFO  on buyer and seller? how could i connect them?